LCOV - code coverage report
Current view: top level - src/backend/postmaster - pgstat.c (source / functions) Hit Total Coverage
Test: PostgreSQL 13devel Lines: 1389 2090 66.5 %
Date: 2019-07-19 13:07:20 Functions: 96 116 82.8 %
Legend: Lines: hit not hit

          Line data    Source code
       1             : /* ----------
       2             :  * pgstat.c
       3             :  *
       4             :  *  All the statistics collector stuff hacked up in one big, ugly file.
       5             :  *
       6             :  *  TODO:   - Separate collector, postmaster and backend stuff
       7             :  *            into different files.
       8             :  *
       9             :  *          - Add some automatic call for pgstat vacuuming.
      10             :  *
      11             :  *          - Add a pgstat config column to pg_database, so this
      12             :  *            entire thing can be enabled/disabled on a per db basis.
      13             :  *
      14             :  *  Copyright (c) 2001-2019, PostgreSQL Global Development Group
      15             :  *
      16             :  *  src/backend/postmaster/pgstat.c
      17             :  * ----------
      18             :  */
      19             : #include "postgres.h"
      20             : 
      21             : #include <unistd.h>
      22             : #include <fcntl.h>
      23             : #include <sys/param.h>
      24             : #include <sys/time.h>
      25             : #include <sys/socket.h>
      26             : #include <netdb.h>
      27             : #include <netinet/in.h>
      28             : #include <arpa/inet.h>
      29             : #include <signal.h>
      30             : #include <time.h>
      31             : #ifdef HAVE_SYS_SELECT_H
      32             : #include <sys/select.h>
      33             : #endif
      34             : 
      35             : #include "pgstat.h"
      36             : 
      37             : #include "access/heapam.h"
      38             : #include "access/htup_details.h"
      39             : #include "access/tableam.h"
      40             : #include "access/transam.h"
      41             : #include "access/twophase_rmgr.h"
      42             : #include "access/xact.h"
      43             : #include "catalog/pg_database.h"
      44             : #include "catalog/pg_proc.h"
      45             : #include "common/ip.h"
      46             : #include "libpq/libpq.h"
      47             : #include "libpq/pqsignal.h"
      48             : #include "mb/pg_wchar.h"
      49             : #include "miscadmin.h"
      50             : #include "pg_trace.h"
      51             : #include "postmaster/autovacuum.h"
      52             : #include "postmaster/fork_process.h"
      53             : #include "postmaster/postmaster.h"
      54             : #include "replication/walsender.h"
      55             : #include "storage/backendid.h"
      56             : #include "storage/dsm.h"
      57             : #include "storage/fd.h"
      58             : #include "storage/ipc.h"
      59             : #include "storage/latch.h"
      60             : #include "storage/lmgr.h"
      61             : #include "storage/pg_shmem.h"
      62             : #include "storage/procsignal.h"
      63             : #include "storage/sinvaladt.h"
      64             : #include "utils/ascii.h"
      65             : #include "utils/guc.h"
      66             : #include "utils/memutils.h"
      67             : #include "utils/ps_status.h"
      68             : #include "utils/rel.h"
      69             : #include "utils/snapmgr.h"
      70             : #include "utils/timestamp.h"
      71             : 
      72             : 
      73             : /* ----------
      74             :  * Timer definitions.
      75             :  * ----------
      76             :  */
      77             : #define PGSTAT_STAT_INTERVAL    500 /* Minimum time between stats file
      78             :                                      * updates; in milliseconds. */
      79             : 
      80             : #define PGSTAT_RETRY_DELAY      10  /* How long to wait between checks for a
      81             :                                      * new file; in milliseconds. */
      82             : 
      83             : #define PGSTAT_MAX_WAIT_TIME    10000   /* Maximum time to wait for a stats
      84             :                                          * file update; in milliseconds. */
      85             : 
      86             : #define PGSTAT_INQ_INTERVAL     640 /* How often to ping the collector for a
      87             :                                      * new file; in milliseconds. */
      88             : 
      89             : #define PGSTAT_RESTART_INTERVAL 60  /* How often to attempt to restart a
      90             :                                      * failed statistics collector; in
      91             :                                      * seconds. */
      92             : 
      93             : #define PGSTAT_POLL_LOOP_COUNT  (PGSTAT_MAX_WAIT_TIME / PGSTAT_RETRY_DELAY)
      94             : #define PGSTAT_INQ_LOOP_COUNT   (PGSTAT_INQ_INTERVAL / PGSTAT_RETRY_DELAY)
      95             : 
      96             : /* Minimum receive buffer size for the collector's socket. */
      97             : #define PGSTAT_MIN_RCVBUF       (100 * 1024)
      98             : 
      99             : 
     100             : /* ----------
     101             :  * The initial size hints for the hash tables used in the collector.
     102             :  * ----------
     103             :  */
     104             : #define PGSTAT_DB_HASH_SIZE     16
     105             : #define PGSTAT_TAB_HASH_SIZE    512
     106             : #define PGSTAT_FUNCTION_HASH_SIZE   512
     107             : 
     108             : 
     109             : /* ----------
     110             :  * Total number of backends including auxiliary
     111             :  *
     112             :  * We reserve a slot for each possible BackendId, plus one for each
     113             :  * possible auxiliary process type.  (This scheme assumes there is not
     114             :  * more than one of any auxiliary process type at a time.) MaxBackends
     115             :  * includes autovacuum workers and background workers as well.
     116             :  * ----------
     117             :  */
     118             : #define NumBackendStatSlots (MaxBackends + NUM_AUXPROCTYPES)
     119             : 
     120             : 
     121             : /* ----------
     122             :  * GUC parameters
     123             :  * ----------
     124             :  */
     125             : bool        pgstat_track_activities = false;
     126             : bool        pgstat_track_counts = false;
     127             : int         pgstat_track_functions = TRACK_FUNC_OFF;
     128             : int         pgstat_track_activity_query_size = 1024;
     129             : 
     130             : /* ----------
     131             :  * Built from GUC parameter
     132             :  * ----------
     133             :  */
     134             : char       *pgstat_stat_directory = NULL;
     135             : char       *pgstat_stat_filename = NULL;
     136             : char       *pgstat_stat_tmpname = NULL;
     137             : 
     138             : /*
     139             :  * BgWriter global statistics counters (unused in other processes).
     140             :  * Stored directly in a stats message structure so it can be sent
     141             :  * without needing to copy things around.  We assume this inits to zeroes.
     142             :  */
     143             : PgStat_MsgBgWriter BgWriterStats;
     144             : 
     145             : /* ----------
     146             :  * Local data
     147             :  * ----------
     148             :  */
     149             : NON_EXEC_STATIC pgsocket pgStatSock = PGINVALID_SOCKET;
     150             : 
     151             : static struct sockaddr_storage pgStatAddr;
     152             : 
     153             : static time_t last_pgstat_start_time;
     154             : 
     155             : static bool pgStatRunningInCollector = false;
     156             : 
     157             : /*
     158             :  * Structures in which backends store per-table info that's waiting to be
     159             :  * sent to the collector.
     160             :  *
     161             :  * NOTE: once allocated, TabStatusArray structures are never moved or deleted
     162             :  * for the life of the backend.  Also, we zero out the t_id fields of the
     163             :  * contained PgStat_TableStatus structs whenever they are not actively in use.
     164             :  * This allows relcache pgstat_info pointers to be treated as long-lived data,
     165             :  * avoiding repeated searches in pgstat_initstats() when a relation is
     166             :  * repeatedly opened during a transaction.
     167             :  */
     168             : #define TABSTAT_QUANTUM     100 /* we alloc this many at a time */
     169             : 
     170             : typedef struct TabStatusArray
     171             : {
     172             :     struct TabStatusArray *tsa_next;    /* link to next array, if any */
     173             :     int         tsa_used;       /* # entries currently used */
     174             :     PgStat_TableStatus tsa_entries[TABSTAT_QUANTUM];    /* per-table data */
     175             : } TabStatusArray;
     176             : 
     177             : static TabStatusArray *pgStatTabList = NULL;
     178             : 
     179             : /*
     180             :  * pgStatTabHash entry: map from relation OID to PgStat_TableStatus pointer
     181             :  */
     182             : typedef struct TabStatHashEntry
     183             : {
     184             :     Oid         t_id;
     185             :     PgStat_TableStatus *tsa_entry;
     186             : } TabStatHashEntry;
     187             : 
     188             : /*
     189             :  * Hash table for O(1) t_id -> tsa_entry lookup
     190             :  */
     191             : static HTAB *pgStatTabHash = NULL;
     192             : 
     193             : /*
     194             :  * Backends store per-function info that's waiting to be sent to the collector
     195             :  * in this hash table (indexed by function OID).
     196             :  */
     197             : static HTAB *pgStatFunctions = NULL;
     198             : 
     199             : /*
     200             :  * Indicates if backend has some function stats that it hasn't yet
     201             :  * sent to the collector.
     202             :  */
     203             : static bool have_function_stats = false;
     204             : 
     205             : /*
     206             :  * Tuple insertion/deletion counts for an open transaction can't be propagated
     207             :  * into PgStat_TableStatus counters until we know if it is going to commit
     208             :  * or abort.  Hence, we keep these counts in per-subxact structs that live
     209             :  * in TopTransactionContext.  This data structure is designed on the assumption
     210             :  * that subxacts won't usually modify very many tables.
     211             :  */
     212             : typedef struct PgStat_SubXactStatus
     213             : {
     214             :     int         nest_level;     /* subtransaction nest level */
     215             :     struct PgStat_SubXactStatus *prev;  /* higher-level subxact if any */
     216             :     PgStat_TableXactStatus *first;  /* head of list for this subxact */
     217             : } PgStat_SubXactStatus;
     218             : 
     219             : static PgStat_SubXactStatus *pgStatXactStack = NULL;
     220             : 
     221             : static int  pgStatXactCommit = 0;
     222             : static int  pgStatXactRollback = 0;
     223             : PgStat_Counter pgStatBlockReadTime = 0;
     224             : PgStat_Counter pgStatBlockWriteTime = 0;
     225             : 
     226             : /* Record that's written to 2PC state file when pgstat state is persisted */
     227             : typedef struct TwoPhasePgStatRecord
     228             : {
     229             :     PgStat_Counter tuples_inserted; /* tuples inserted in xact */
     230             :     PgStat_Counter tuples_updated;  /* tuples updated in xact */
     231             :     PgStat_Counter tuples_deleted;  /* tuples deleted in xact */
     232             :     PgStat_Counter inserted_pre_trunc;  /* tuples inserted prior to truncate */
     233             :     PgStat_Counter updated_pre_trunc;   /* tuples updated prior to truncate */
     234             :     PgStat_Counter deleted_pre_trunc;   /* tuples deleted prior to truncate */
     235             :     Oid         t_id;           /* table's OID */
     236             :     bool        t_shared;       /* is it a shared catalog? */
     237             :     bool        t_truncated;    /* was the relation truncated? */
     238             : } TwoPhasePgStatRecord;
     239             : 
     240             : /*
     241             :  * Info about current "snapshot" of stats file
     242             :  */
     243             : static MemoryContext pgStatLocalContext = NULL;
     244             : static HTAB *pgStatDBHash = NULL;
     245             : 
     246             : /* Status for backends including auxiliary */
     247             : static LocalPgBackendStatus *localBackendStatusTable = NULL;
     248             : 
     249             : /* Total number of backends including auxiliary */
     250             : static int  localNumBackends = 0;
     251             : 
     252             : /*
     253             :  * Cluster wide statistics, kept in the stats collector.
     254             :  * Contains statistics that are not collected per database
     255             :  * or per table.
     256             :  */
     257             : static PgStat_ArchiverStats archiverStats;
     258             : static PgStat_GlobalStats globalStats;
     259             : 
     260             : /*
     261             :  * List of OIDs of databases we need to write out.  If an entry is InvalidOid,
     262             :  * it means to write only the shared-catalog stats ("DB 0"); otherwise, we
     263             :  * will write both that DB's data and the shared stats.
     264             :  */
     265             : static List *pending_write_requests = NIL;
     266             : 
     267             : /* Signal handler flags */
     268             : static volatile bool need_exit = false;
     269             : static volatile bool got_SIGHUP = false;
     270             : 
     271             : /*
     272             :  * Total time charged to functions so far in the current backend.
     273             :  * We use this to help separate "self" and "other" time charges.
     274             :  * (We assume this initializes to zero.)
     275             :  */
     276             : static instr_time total_func_time;
     277             : 
     278             : 
     279             : /* ----------
     280             :  * Local function forward declarations
     281             :  * ----------
     282             :  */
     283             : #ifdef EXEC_BACKEND
     284             : static pid_t pgstat_forkexec(void);
     285             : #endif
     286             : 
     287             : NON_EXEC_STATIC void PgstatCollectorMain(int argc, char *argv[]) pg_attribute_noreturn();
     288             : static void pgstat_exit(SIGNAL_ARGS);
     289             : static void pgstat_beshutdown_hook(int code, Datum arg);
     290             : static void pgstat_sighup_handler(SIGNAL_ARGS);
     291             : 
     292             : static PgStat_StatDBEntry *pgstat_get_db_entry(Oid databaseid, bool create);
     293             : static PgStat_StatTabEntry *pgstat_get_tab_entry(PgStat_StatDBEntry *dbentry,
     294             :                                                  Oid tableoid, bool create);
     295             : static void pgstat_write_statsfiles(bool permanent, bool allDbs);
     296             : static void pgstat_write_db_statsfile(PgStat_StatDBEntry *dbentry, bool permanent);
     297             : static HTAB *pgstat_read_statsfiles(Oid onlydb, bool permanent, bool deep);
     298             : static void pgstat_read_db_statsfile(Oid databaseid, HTAB *tabhash, HTAB *funchash, bool permanent);
     299             : static void backend_read_statsfile(void);
     300             : static void pgstat_read_current_status(void);
     301             : 
     302             : static bool pgstat_write_statsfile_needed(void);
     303             : static bool pgstat_db_requested(Oid databaseid);
     304             : 
     305             : static void pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg);
     306             : static void pgstat_send_funcstats(void);
     307             : static HTAB *pgstat_collect_oids(Oid catalogid, AttrNumber anum_oid);
     308             : 
     309             : static PgStat_TableStatus *get_tabstat_entry(Oid rel_id, bool isshared);
     310             : 
     311             : static void pgstat_setup_memcxt(void);
     312             : 
     313             : static const char *pgstat_get_wait_activity(WaitEventActivity w);
     314             : static const char *pgstat_get_wait_client(WaitEventClient w);
     315             : static const char *pgstat_get_wait_ipc(WaitEventIPC w);
     316             : static const char *pgstat_get_wait_timeout(WaitEventTimeout w);
     317             : static const char *pgstat_get_wait_io(WaitEventIO w);
     318             : 
     319             : static void pgstat_setheader(PgStat_MsgHdr *hdr, StatMsgType mtype);
     320             : static void pgstat_send(void *msg, int len);
     321             : 
     322             : static void pgstat_recv_inquiry(PgStat_MsgInquiry *msg, int len);
     323             : static void pgstat_recv_tabstat(PgStat_MsgTabstat *msg, int len);
     324             : static void pgstat_recv_tabpurge(PgStat_MsgTabpurge *msg, int len);
     325             : static void pgstat_recv_dropdb(PgStat_MsgDropdb *msg, int len);
     326             : static void pgstat_recv_resetcounter(PgStat_MsgResetcounter *msg, int len);
     327             : static void pgstat_recv_resetsharedcounter(PgStat_MsgResetsharedcounter *msg, int len);
     328             : static void pgstat_recv_resetsinglecounter(PgStat_MsgResetsinglecounter *msg, int len);
     329             : static void pgstat_recv_autovac(PgStat_MsgAutovacStart *msg, int len);
     330             : static void pgstat_recv_vacuum(PgStat_MsgVacuum *msg, int len);
     331             : static void pgstat_recv_analyze(PgStat_MsgAnalyze *msg, int len);
     332             : static void pgstat_recv_archiver(PgStat_MsgArchiver *msg, int len);
     333             : static void pgstat_recv_bgwriter(PgStat_MsgBgWriter *msg, int len);
     334             : static void pgstat_recv_funcstat(PgStat_MsgFuncstat *msg, int len);
     335             : static void pgstat_recv_funcpurge(PgStat_MsgFuncpurge *msg, int len);
     336             : static void pgstat_recv_recoveryconflict(PgStat_MsgRecoveryConflict *msg, int len);
     337             : static void pgstat_recv_deadlock(PgStat_MsgDeadlock *msg, int len);
     338             : static void pgstat_recv_checksum_failure(PgStat_MsgChecksumFailure *msg, int len);
     339             : static void pgstat_recv_tempfile(PgStat_MsgTempFile *msg, int len);
     340             : 
     341             : /* ------------------------------------------------------------
     342             :  * Public functions called from postmaster follow
     343             :  * ------------------------------------------------------------
     344             :  */
     345             : 
     346             : /* ----------
     347             :  * pgstat_init() -
     348             :  *
     349             :  *  Called from postmaster at startup. Create the resources required
     350             :  *  by the statistics collector process.  If unable to do so, do not
     351             :  *  fail --- better to let the postmaster start with stats collection
     352             :  *  disabled.
     353             :  * ----------
     354             :  */
     355             : void
     356         574 : pgstat_init(void)
     357             : {
     358             :     ACCEPT_TYPE_ARG3 alen;
     359         574 :     struct addrinfo *addrs = NULL,
     360             :                *addr,
     361             :                 hints;
     362             :     int         ret;
     363             :     fd_set      rset;
     364             :     struct timeval tv;
     365             :     char        test_byte;
     366             :     int         sel_res;
     367         574 :     int         tries = 0;
     368             : 
     369             : #define TESTBYTEVAL ((char) 199)
     370             : 
     371             :     /*
     372             :      * This static assertion verifies that we didn't mess up the calculations
     373             :      * involved in selecting maximum payload sizes for our UDP messages.
     374             :      * Because the only consequence of overrunning PGSTAT_MAX_MSG_SIZE would
     375             :      * be silent performance loss from fragmentation, it seems worth having a
     376             :      * compile-time cross-check that we didn't.
     377             :      */
     378             :     StaticAssertStmt(sizeof(PgStat_Msg) <= PGSTAT_MAX_MSG_SIZE,
     379             :                      "maximum stats message size exceeds PGSTAT_MAX_MSG_SIZE");
     380             : 
     381             :     /*
     382             :      * Create the UDP socket for sending and receiving statistic messages
     383             :      */
     384         574 :     hints.ai_flags = AI_PASSIVE;
     385         574 :     hints.ai_family = AF_UNSPEC;
     386         574 :     hints.ai_socktype = SOCK_DGRAM;
     387         574 :     hints.ai_protocol = 0;
     388         574 :     hints.ai_addrlen = 0;
     389         574 :     hints.ai_addr = NULL;
     390         574 :     hints.ai_canonname = NULL;
     391         574 :     hints.ai_next = NULL;
     392         574 :     ret = pg_getaddrinfo_all("localhost", NULL, &hints, &addrs);
     393         574 :     if (ret || !addrs)
     394             :     {
     395           0 :         ereport(LOG,
     396             :                 (errmsg("could not resolve \"localhost\": %s",
     397             :                         gai_strerror(ret))));
     398           0 :         goto startup_failed;
     399             :     }
     400             : 
     401             :     /*
     402             :      * On some platforms, pg_getaddrinfo_all() may return multiple addresses
     403             :      * only one of which will actually work (eg, both IPv6 and IPv4 addresses
     404             :      * when kernel will reject IPv6).  Worse, the failure may occur at the
     405             :      * bind() or perhaps even connect() stage.  So we must loop through the
     406             :      * results till we find a working combination. We will generate LOG
     407             :      * messages, but no error, for bogus combinations.
     408             :      */
     409         574 :     for (addr = addrs; addr; addr = addr->ai_next)
     410             :     {
     411             : #ifdef HAVE_UNIX_SOCKETS
     412             :         /* Ignore AF_UNIX sockets, if any are returned. */
     413         574 :         if (addr->ai_family == AF_UNIX)
     414           0 :             continue;
     415             : #endif
     416             : 
     417         574 :         if (++tries > 1)
     418           0 :             ereport(LOG,
     419             :                     (errmsg("trying another address for the statistics collector")));
     420             : 
     421             :         /*
     422             :          * Create the socket.
     423             :          */
     424         574 :         if ((pgStatSock = socket(addr->ai_family, SOCK_DGRAM, 0)) == PGINVALID_SOCKET)
     425             :         {
     426           0 :             ereport(LOG,
     427             :                     (errcode_for_socket_access(),
     428             :                      errmsg("could not create socket for statistics collector: %m")));
     429           0 :             continue;
     430             :         }
     431             : 
     432             :         /*
     433             :          * Bind it to a kernel assigned port on localhost and get the assigned
     434             :          * port via getsockname().
     435             :          */
     436         574 :         if (bind(pgStatSock, addr->ai_addr, addr->ai_addrlen) < 0)
     437             :         {
     438           0 :             ereport(LOG,
     439             :                     (errcode_for_socket_access(),
     440             :                      errmsg("could not bind socket for statistics collector: %m")));
     441           0 :             closesocket(pgStatSock);
     442           0 :             pgStatSock = PGINVALID_SOCKET;
     443           0 :             continue;
     444             :         }
     445             : 
     446         574 :         alen = sizeof(pgStatAddr);
     447         574 :         if (getsockname(pgStatSock, (struct sockaddr *) &pgStatAddr, &alen) < 0)
     448             :         {
     449           0 :             ereport(LOG,
     450             :                     (errcode_for_socket_access(),
     451             :                      errmsg("could not get address of socket for statistics collector: %m")));
     452           0 :             closesocket(pgStatSock);
     453           0 :             pgStatSock = PGINVALID_SOCKET;
     454           0 :             continue;
     455             :         }
     456             : 
     457             :         /*
     458             :          * Connect the socket to its own address.  This saves a few cycles by
     459             :          * not having to respecify the target address on every send. This also
     460             :          * provides a kernel-level check that only packets from this same
     461             :          * address will be received.
     462             :          */
     463         574 :         if (connect(pgStatSock, (struct sockaddr *) &pgStatAddr, alen) < 0)
     464             :         {
     465           0 :             ereport(LOG,
     466             :                     (errcode_for_socket_access(),
     467             :                      errmsg("could not connect socket for statistics collector: %m")));
     468           0 :             closesocket(pgStatSock);
     469           0 :             pgStatSock = PGINVALID_SOCKET;
     470           0 :             continue;
     471             :         }
     472             : 
     473             :         /*
     474             :          * Try to send and receive a one-byte test message on the socket. This
     475             :          * is to catch situations where the socket can be created but will not
     476             :          * actually pass data (for instance, because kernel packet filtering
     477             :          * rules prevent it).
     478             :          */
     479         574 :         test_byte = TESTBYTEVAL;
     480             : 
     481             : retry1:
     482         574 :         if (send(pgStatSock, &test_byte, 1, 0) != 1)
     483             :         {
     484           0 :             if (errno == EINTR)
     485           0 :                 goto retry1;    /* if interrupted, just retry */
     486           0 :             ereport(LOG,
     487             :                     (errcode_for_socket_access(),
     488             :                      errmsg("could not send test message on socket for statistics collector: %m")));
     489           0 :             closesocket(pgStatSock);
     490           0 :             pgStatSock = PGINVALID_SOCKET;
     491           0 :             continue;
     492             :         }
     493             : 
     494             :         /*
     495             :          * There could possibly be a little delay before the message can be
     496             :          * received.  We arbitrarily allow up to half a second before deciding
     497             :          * it's broken.
     498             :          */
     499             :         for (;;)                /* need a loop to handle EINTR */
     500             :         {
     501         574 :             FD_ZERO(&rset);
     502         574 :             FD_SET(pgStatSock, &rset);
     503             : 
     504         574 :             tv.tv_sec = 0;
     505         574 :             tv.tv_usec = 500000;
     506         574 :             sel_res = select(pgStatSock + 1, &rset, NULL, NULL, &tv);
     507         574 :             if (sel_res >= 0 || errno != EINTR)
     508             :                 break;
     509             :         }
     510         574 :         if (sel_res < 0)
     511             :         {
     512           0 :             ereport(LOG,
     513             :                     (errcode_for_socket_access(),
     514             :                      errmsg("select() failed in statistics collector: %m")));
     515           0 :             closesocket(pgStatSock);
     516           0 :             pgStatSock = PGINVALID_SOCKET;
     517           0 :             continue;
     518             :         }
     519         574 :         if (sel_res == 0 || !FD_ISSET(pgStatSock, &rset))
     520             :         {
     521             :             /*
     522             :              * This is the case we actually think is likely, so take pains to
     523             :              * give a specific message for it.
     524             :              *
     525             :              * errno will not be set meaningfully here, so don't use it.
     526             :              */
     527           0 :             ereport(LOG,
     528             :                     (errcode(ERRCODE_CONNECTION_FAILURE),
     529             :                      errmsg("test message did not get through on socket for statistics collector")));
     530           0 :             closesocket(pgStatSock);
     531           0 :             pgStatSock = PGINVALID_SOCKET;
     532           0 :             continue;
     533             :         }
     534             : 
     535         574 :         test_byte++;            /* just make sure variable is changed */
     536             : 
     537             : retry2:
     538         574 :         if (recv(pgStatSock, &test_byte, 1, 0) != 1)
     539             :         {
     540           0 :             if (errno == EINTR)
     541           0 :                 goto retry2;    /* if interrupted, just retry */
     542           0 :             ereport(LOG,
     543             :                     (errcode_for_socket_access(),
     544             :                      errmsg("could not receive test message on socket for statistics collector: %m")));
     545           0 :             closesocket(pgStatSock);
     546           0 :             pgStatSock = PGINVALID_SOCKET;
     547           0 :             continue;
     548             :         }
     549             : 
     550         574 :         if (test_byte != TESTBYTEVAL)   /* strictly paranoia ... */
     551             :         {
     552           0 :             ereport(LOG,
     553             :                     (errcode(ERRCODE_INTERNAL_ERROR),
     554             :                      errmsg("incorrect test message transmission on socket for statistics collector")));
     555           0 :             closesocket(pgStatSock);
     556           0 :             pgStatSock = PGINVALID_SOCKET;
     557           0 :             continue;
     558             :         }
     559             : 
     560             :         /* If we get here, we have a working socket */
     561         574 :         break;
     562             :     }
     563             : 
     564             :     /* Did we find a working address? */
     565         574 :     if (!addr || pgStatSock == PGINVALID_SOCKET)
     566             :         goto startup_failed;
     567             : 
     568             :     /*
     569             :      * Set the socket to non-blocking IO.  This ensures that if the collector
     570             :      * falls behind, statistics messages will be discarded; backends won't
     571             :      * block waiting to send messages to the collector.
     572             :      */
     573         574 :     if (!pg_set_noblock(pgStatSock))
     574             :     {
     575           0 :         ereport(LOG,
     576             :                 (errcode_for_socket_access(),
     577             :                  errmsg("could not set statistics collector socket to nonblocking mode: %m")));
     578           0 :         goto startup_failed;
     579             :     }
     580             : 
     581             :     /*
     582             :      * Try to ensure that the socket's receive buffer is at least
     583             :      * PGSTAT_MIN_RCVBUF bytes, so that it won't easily overflow and lose
     584             :      * data.  Use of UDP protocol means that we are willing to lose data under
     585             :      * heavy load, but we don't want it to happen just because of ridiculously
     586             :      * small default buffer sizes (such as 8KB on older Windows versions).
     587             :      */
     588             :     {
     589             :         int         old_rcvbuf;
     590             :         int         new_rcvbuf;
     591         574 :         ACCEPT_TYPE_ARG3 rcvbufsize = sizeof(old_rcvbuf);
     592             : 
     593         574 :         if (getsockopt(pgStatSock, SOL_SOCKET, SO_RCVBUF,
     594             :                        (char *) &old_rcvbuf, &rcvbufsize) < 0)
     595             :         {
     596           0 :             elog(LOG, "getsockopt(SO_RCVBUF) failed: %m");
     597             :             /* if we can't get existing size, always try to set it */
     598           0 :             old_rcvbuf = 0;
     599             :         }
     600             : 
     601         574 :         new_rcvbuf = PGSTAT_MIN_RCVBUF;
     602         574 :         if (old_rcvbuf < new_rcvbuf)
     603             :         {
     604           0 :             if (setsockopt(pgStatSock, SOL_SOCKET, SO_RCVBUF,
     605             :                            (char *) &new_rcvbuf, sizeof(new_rcvbuf)) < 0)
     606           0 :                 elog(LOG, "setsockopt(SO_RCVBUF) failed: %m");
     607             :         }
     608             :     }
     609             : 
     610         574 :     pg_freeaddrinfo_all(hints.ai_family, addrs);
     611             : 
     612         574 :     return;
     613             : 
     614             : startup_failed:
     615           0 :     ereport(LOG,
     616             :             (errmsg("disabling statistics collector for lack of working socket")));
     617             : 
     618           0 :     if (addrs)
     619           0 :         pg_freeaddrinfo_all(hints.ai_family, addrs);
     620             : 
     621           0 :     if (pgStatSock != PGINVALID_SOCKET)
     622           0 :         closesocket(pgStatSock);
     623           0 :     pgStatSock = PGINVALID_SOCKET;
     624             : 
     625             :     /*
     626             :      * Adjust GUC variables to suppress useless activity, and for debugging
     627             :      * purposes (seeing track_counts off is a clue that we failed here). We
     628             :      * use PGC_S_OVERRIDE because there is no point in trying to turn it back
     629             :      * on from postgresql.conf without a restart.
     630             :      */
     631           0 :     SetConfigOption("track_counts", "off", PGC_INTERNAL, PGC_S_OVERRIDE);
     632             : }
     633             : 
     634             : /*
     635             :  * subroutine for pgstat_reset_all
     636             :  */
     637             : static void
     638         184 : pgstat_reset_remove_files(const char *directory)
     639             : {
     640             :     DIR        *dir;
     641             :     struct dirent *entry;
     642             :     char        fname[MAXPGPATH * 2];
     643             : 
     644         184 :     dir = AllocateDir(directory);
     645         848 :     while ((entry = ReadDir(dir, directory)) != NULL)
     646             :     {
     647             :         int         nchars;
     648             :         Oid         tmp_oid;
     649             : 
     650             :         /*
     651             :          * Skip directory entries that don't match the file names we write.
     652             :          * See get_dbstat_filename for the database-specific pattern.
     653             :          */
     654         480 :         if (strncmp(entry->d_name, "global.", 7) == 0)
     655          44 :             nchars = 7;
     656             :         else
     657             :         {
     658         436 :             nchars = 0;
     659         436 :             (void) sscanf(entry->d_name, "db_%u.%n",
     660             :                           &tmp_oid, &nchars);
     661         436 :             if (nchars <= 0)
     662         736 :                 continue;
     663             :             /* %u allows leading whitespace, so reject that */
     664          68 :             if (strchr("0123456789", entry->d_name[3]) == NULL)
     665           0 :                 continue;
     666             :         }
     667             : 
     668         224 :         if (strcmp(entry->d_name + nchars, "tmp") != 0 &&
     669         112 :             strcmp(entry->d_name + nchars, "stat") != 0)
     670           0 :             continue;
     671             : 
     672         112 :         snprintf(fname, sizeof(fname), "%s/%s", directory,
     673         112 :                  entry->d_name);
     674         112 :         unlink(fname);
     675             :     }
     676         184 :     FreeDir(dir);
     677         184 : }
     678             : 
     679             : /*
     680             :  * pgstat_reset_all() -
     681             :  *
     682             :  * Remove the stats files.  This is currently used only if WAL
     683             :  * recovery is needed after a crash.
     684             :  */
     685             : void
     686          92 : pgstat_reset_all(void)
     687             : {
     688          92 :     pgstat_reset_remove_files(pgstat_stat_directory);
     689          92 :     pgstat_reset_remove_files(PGSTAT_STAT_PERMANENT_DIRECTORY);
     690          92 : }
     691             : 
     692             : #ifdef EXEC_BACKEND
     693             : 
     694             : /*
     695             :  * pgstat_forkexec() -
     696             :  *
     697             :  * Format up the arglist for, then fork and exec, statistics collector process
     698             :  */
     699             : static pid_t
     700             : pgstat_forkexec(void)
     701             : {
     702             :     char       *av[10];
     703             :     int         ac = 0;
     704             : 
     705             :     av[ac++] = "postgres";
     706             :     av[ac++] = "--forkcol";
     707             :     av[ac++] = NULL;            /* filled in by postmaster_forkexec */
     708             : 
     709             :     av[ac] = NULL;
     710             :     Assert(ac < lengthof(av));
     711             : 
     712             :     return postmaster_forkexec(ac, av);
     713             : }
     714             : #endif                          /* EXEC_BACKEND */
     715             : 
     716             : 
     717             : /*
     718             :  * pgstat_start() -
     719             :  *
     720             :  *  Called from postmaster at startup or after an existing collector
     721             :  *  died.  Attempt to fire up a fresh statistics collector.
     722             :  *
     723             :  *  Returns PID of child process, or 0 if fail.
     724             :  *
     725             :  *  Note: if fail, we will be called again from the postmaster main loop.
     726             :  */
     727             : int
     728         578 : pgstat_start(void)
     729             : {
     730             :     time_t      curtime;
     731             :     pid_t       pgStatPid;
     732             : 
     733             :     /*
     734             :      * Check that the socket is there, else pgstat_init failed and we can do
     735             :      * nothing useful.
     736             :      */
     737         578 :     if (pgStatSock == PGINVALID_SOCKET)
     738           0 :         return 0;
     739             : 
     740             :     /*
     741             :      * Do nothing if too soon since last collector start.  This is a safety
     742             :      * valve to protect against continuous respawn attempts if the collector
     743             :      * is dying immediately at launch.  Note that since we will be re-called
     744             :      * from the postmaster main loop, we will get another chance later.
     745             :      */
     746         578 :     curtime = time(NULL);
     747         578 :     if ((unsigned int) (curtime - last_pgstat_start_time) <
     748             :         (unsigned int) PGSTAT_RESTART_INTERVAL)
     749           0 :         return 0;
     750         578 :     last_pgstat_start_time = curtime;
     751             : 
     752             :     /*
     753             :      * Okay, fork off the collector.
     754             :      */
     755             : #ifdef EXEC_BACKEND
     756             :     switch ((pgStatPid = pgstat_forkexec()))
     757             : #else
     758         578 :     switch ((pgStatPid = fork_process()))
     759             : #endif
     760             :     {
     761             :         case -1:
     762           0 :             ereport(LOG,
     763             :                     (errmsg("could not fork statistics collector: %m")));
     764           0 :             return 0;
     765             : 
     766             : #ifndef EXEC_BACKEND
     767             :         case 0:
     768             :             /* in postmaster child ... */
     769         578 :             InitPostmasterChild();
     770             : 
     771             :             /* Close the postmaster's sockets */
     772         578 :             ClosePostmasterPorts(false);
     773             : 
     774             :             /* Drop our connection to postmaster's shared memory, as well */
     775         578 :             dsm_detach_all();
     776         578 :             PGSharedMemoryDetach();
     777             : 
     778         578 :             PgstatCollectorMain(0, NULL);
     779             :             break;
     780             : #endif
     781             : 
     782             :         default:
     783         578 :             return (int) pgStatPid;
     784             :     }
     785             : 
     786             :     /* shouldn't get here */
     787             :     return 0;
     788             : }
     789             : 
     790             : void
     791           4 : allow_immediate_pgstat_restart(void)
     792             : {
     793           4 :     last_pgstat_start_time = 0;
     794           4 : }
     795             : 
     796             : /* ------------------------------------------------------------
     797             :  * Public functions used by backends follow
     798             :  *------------------------------------------------------------
     799             :  */
     800             : 
     801             : 
     802             : /* ----------
     803             :  * pgstat_report_stat() -
     804             :  *
     805             :  *  Must be called by processes that performs DML: tcop/postgres.c, logical
     806             :  *  receiver processes, SPI worker, etc. to send the so far collected
     807             :  *  per-table and function usage statistics to the collector.  Note that this
     808             :  *  is called only when not within a transaction, so it is fair to use
     809             :  *  transaction stop time as an approximation of current time.
     810             :  * ----------
     811             :  */
     812             : void
     813      379812 : pgstat_report_stat(bool force)
     814             : {
     815             :     /* we assume this inits to all zeroes: */
     816             :     static const PgStat_TableCounts all_zeroes;
     817             :     static TimestampTz last_report = 0;
     818             : 
     819             :     TimestampTz now;
     820             :     PgStat_MsgTabstat regular_msg;
     821             :     PgStat_MsgTabstat shared_msg;
     822             :     TabStatusArray *tsa;
     823             :     int         i;
     824             : 
     825             :     /* Don't expend a clock check if nothing to do */
     826      544936 :     if ((pgStatTabList == NULL || pgStatTabList->tsa_used == 0) &&
     827      166188 :         pgStatXactCommit == 0 && pgStatXactRollback == 0 &&
     828         520 :         !have_function_stats)
     829      362800 :         return;
     830             : 
     831             :     /*
     832             :      * Don't send a message unless it's been at least PGSTAT_STAT_INTERVAL
     833             :      * msec since we last sent one, or the caller wants to force stats out.
     834             :      */
     835      379292 :     now = GetCurrentTransactionStopTimestamp();
     836      750696 :     if (!force &&
     837      371404 :         !TimestampDifferenceExceeds(last_report, now, PGSTAT_STAT_INTERVAL))
     838      361760 :         return;
     839       17532 :     last_report = now;
     840             : 
     841             :     /*
     842             :      * Destroy pgStatTabHash before we start invalidating PgStat_TableEntry
     843             :      * entries it points to.  (Should we fail partway through the loop below,
     844             :      * it's okay to have removed the hashtable already --- the only
     845             :      * consequence is we'd get multiple entries for the same table in the
     846             :      * pgStatTabList, and that's safe.)
     847             :      */
     848       17532 :     if (pgStatTabHash)
     849       15690 :         hash_destroy(pgStatTabHash);
     850       17532 :     pgStatTabHash = NULL;
     851             : 
     852             :     /*
     853             :      * Scan through the TabStatusArray struct(s) to find tables that actually
     854             :      * have counts, and build messages to send.  We have to separate shared
     855             :      * relations from regular ones because the databaseid field in the message
     856             :      * header has to depend on that.
     857             :      */
     858       17532 :     regular_msg.m_databaseid = MyDatabaseId;
     859       17532 :     shared_msg.m_databaseid = InvalidOid;
     860       17532 :     regular_msg.m_nentries = 0;
     861       17532 :     shared_msg.m_nentries = 0;
     862             : 
     863       36630 :     for (tsa = pgStatTabList; tsa != NULL; tsa = tsa->tsa_next)
     864             :     {
     865      683406 :         for (i = 0; i < tsa->tsa_used; i++)
     866             :         {
     867      664308 :             PgStat_TableStatus *entry = &tsa->tsa_entries[i];
     868             :             PgStat_MsgTabstat *this_msg;
     869             :             PgStat_TableEntry *this_ent;
     870             : 
     871             :             /* Shouldn't have any pending transaction-dependent counts */
     872             :             Assert(entry->trans == NULL);
     873             : 
     874             :             /*
     875             :              * Ignore entries that didn't accumulate any actual counts, such
     876             :              * as indexes that were opened by the planner but not used.
     877             :              */
     878      664308 :             if (memcmp(&entry->t_counts, &all_zeroes,
     879             :                        sizeof(PgStat_TableCounts)) == 0)
     880      169788 :                 continue;
     881             : 
     882             :             /*
     883             :              * OK, insert data into the appropriate message, and send if full.
     884             :              */
     885      494520 :             this_msg = entry->t_shared ? &shared_msg : &regular_msg;
     886      494520 :             this_ent = &this_msg->m_entry[this_msg->m_nentries];
     887      494520 :             this_ent->t_id = entry->t_id;
     888      494520 :             memcpy(&this_ent->t_counts, &entry->t_counts,
     889             :                    sizeof(PgStat_TableCounts));
     890      494520 :             if (++this_msg->m_nentries >= PGSTAT_NUM_TABENTRIES)
     891             :             {
     892       50176 :                 pgstat_send_tabstat(this_msg);
     893       50176 :                 this_msg->m_nentries = 0;
     894             :             }
     895             :         }
     896             :         /* zero out TableStatus structs after use */
     897       19098 :         MemSet(tsa->tsa_entries, 0,
     898             :                tsa->tsa_used * sizeof(PgStat_TableStatus));
     899       19098 :         tsa->tsa_used = 0;
     900             :     }
     901             : 
     902             :     /*
     903             :      * Send partial messages.  Make sure that any pending xact commit/abort
     904             :      * gets counted, even if there are no table stats to send.
     905             :      */
     906       20986 :     if (regular_msg.m_nentries > 0 ||
     907        4782 :         pgStatXactCommit > 0 || pgStatXactRollback > 0)
     908       16212 :         pgstat_send_tabstat(&regular_msg);
     909       17532 :     if (shared_msg.m_nentries > 0)
     910        9596 :         pgstat_send_tabstat(&shared_msg);
     911             : 
     912             :     /* Now, send function statistics */
     913       17532 :     pgstat_send_funcstats();
     914             : }
     915             : 
     916             : /*
     917             :  * Subroutine for pgstat_report_stat: finish and send a tabstat message
     918             :  */
     919             : static void
     920       75984 : pgstat_send_tabstat(PgStat_MsgTabstat *tsmsg)
     921             : {
     922             :     int         n;
     923             :     int         len;
     924             : 
     925             :     /* It's unlikely we'd get here with no socket, but maybe not impossible */
     926       75984 :     if (pgStatSock == PGINVALID_SOCKET)
     927        1442 :         return;
     928             : 
     929             :     /*
     930             :      * Report and reset accumulated xact commit/rollback and I/O timings
     931             :      * whenever we send a normal tabstat message
     932             :      */
     933       74542 :     if (OidIsValid(tsmsg->m_databaseid))
     934             :     {
     935       59448 :         tsmsg->m_xact_commit = pgStatXactCommit;
     936       59448 :         tsmsg->m_xact_rollback = pgStatXactRollback;
     937       59448 :         tsmsg->m_block_read_time = pgStatBlockReadTime;
     938       59448 :         tsmsg->m_block_write_time = pgStatBlockWriteTime;
     939       59448 :         pgStatXactCommit = 0;
     940       59448 :         pgStatXactRollback = 0;
     941       59448 :         pgStatBlockReadTime = 0;
     942       59448 :         pgStatBlockWriteTime = 0;
     943             :     }
     944             :     else
     945             :     {
     946       15094 :         tsmsg->m_xact_commit = 0;
     947       15094 :         tsmsg->m_xact_rollback = 0;
     948       15094 :         tsmsg->m_block_read_time = 0;
     949       15094 :         tsmsg->m_block_write_time = 0;
     950             :     }
     951             : 
     952       74542 :     n = tsmsg->m_nentries;
     953       74542 :     len = offsetof(PgStat_MsgTabstat, m_entry[0]) +
     954             :         n * sizeof(PgStat_TableEntry);
     955             : 
     956       74542 :     pgstat_setheader(&tsmsg->m_hdr, PGSTAT_MTYPE_TABSTAT);
     957       74542 :     pgstat_send(tsmsg, len);
     958             : }
     959             : 
     960             : /*
     961             :  * Subroutine for pgstat_report_stat: populate and send a function stat message
     962             :  */
     963             : static void
     964       17532 : pgstat_send_funcstats(void)
     965             : {
     966             :     /* we assume this inits to all zeroes: */
     967             :     static const PgStat_FunctionCounts all_zeroes;
     968             : 
     969             :     PgStat_MsgFuncstat msg;
     970             :     PgStat_BackendFunctionEntry *entry;
     971             :     HASH_SEQ_STATUS fstat;
     972             : 
     973       17532 :     if (pgStatFunctions == NULL)
     974       17532 :         return;
     975             : 
     976           0 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_FUNCSTAT);
     977           0 :     msg.m_databaseid = MyDatabaseId;
     978           0 :     msg.m_nentries = 0;
     979             : 
     980           0 :     hash_seq_init(&fstat, pgStatFunctions);
     981           0 :     while ((entry = (PgStat_BackendFunctionEntry *) hash_seq_search(&fstat)) != NULL)
     982             :     {
     983             :         PgStat_FunctionEntry *m_ent;
     984             : 
     985             :         /* Skip it if no counts accumulated since last time */
     986           0 :         if (memcmp(&entry->f_counts, &all_zeroes,
     987             :                    sizeof(PgStat_FunctionCounts)) == 0)
     988           0 :             continue;
     989             : 
     990             :         /* need to convert format of time accumulators */
     991           0 :         m_ent = &msg.m_entry[msg.m_nentries];
     992           0 :         m_ent->f_id = entry->f_id;
     993           0 :         m_ent->f_numcalls = entry->f_counts.f_numcalls;
     994           0 :         m_ent->f_total_time = INSTR_TIME_GET_MICROSEC(entry->f_counts.f_total_time);
     995           0 :         m_ent->f_self_time = INSTR_TIME_GET_MICROSEC(entry->f_counts.f_self_time);
     996             : 
     997           0 :         if (++msg.m_nentries >= PGSTAT_NUM_FUNCENTRIES)
     998             :         {
     999           0 :             pgstat_send(&msg, offsetof(PgStat_MsgFuncstat, m_entry[0]) +
    1000           0 :                         msg.m_nentries * sizeof(PgStat_FunctionEntry));
    1001           0 :             msg.m_nentries = 0;
    1002             :         }
    1003             : 
    1004             :         /* reset the entry's counts */
    1005           0 :         MemSet(&entry->f_counts, 0, sizeof(PgStat_FunctionCounts));
    1006             :     }
    1007             : 
    1008           0 :     if (msg.m_nentries > 0)
    1009           0 :         pgstat_send(&msg, offsetof(PgStat_MsgFuncstat, m_entry[0]) +
    1010           0 :                     msg.m_nentries * sizeof(PgStat_FunctionEntry));
    1011             : 
    1012           0 :     have_function_stats = false;
    1013             : }
    1014             : 
    1015             : 
    1016             : /* ----------
    1017             :  * pgstat_vacuum_stat() -
    1018             :  *
    1019             :  *  Will tell the collector about objects he can get rid of.
    1020             :  * ----------
    1021             :  */
    1022             : void
    1023        3648 : pgstat_vacuum_stat(void)
    1024             : {
    1025             :     HTAB       *htab;
    1026             :     PgStat_MsgTabpurge msg;
    1027             :     PgStat_MsgFuncpurge f_msg;
    1028             :     HASH_SEQ_STATUS hstat;
    1029             :     PgStat_StatDBEntry *dbentry;
    1030             :     PgStat_StatTabEntry *tabentry;
    1031             :     PgStat_StatFuncEntry *funcentry;
    1032             :     int         len;
    1033             : 
    1034        3648 :     if (pgStatSock == PGINVALID_SOCKET)
    1035        2980 :         return;
    1036             : 
    1037             :     /*
    1038             :      * If not done for this transaction, read the statistics collector stats
    1039             :      * file into some hash tables.
    1040             :      */
    1041        2368 :     backend_read_statsfile();
    1042             : 
    1043             :     /*
    1044             :      * Read pg_database and make a list of OIDs of all existing databases
    1045             :      */
    1046        2368 :     htab = pgstat_collect_oids(DatabaseRelationId, Anum_pg_database_oid);
    1047             : 
    1048             :     /*
    1049             :      * Search the database hash table for dead databases and tell the
    1050             :      * collector to drop them.
    1051             :      */
    1052        2368 :     hash_seq_init(&hstat, pgStatDBHash);
    1053        9838 :     while ((dbentry = (PgStat_StatDBEntry *) hash_seq_search(&hstat)) != NULL)
    1054             :     {
    1055        5102 :         Oid         dbid = dbentry->databaseid;
    1056             : 
    1057        5102 :         CHECK_FOR_INTERRUPTS();
    1058             : 
    1059             :         /* the DB entry for shared tables (with InvalidOid) is never dropped */
    1060        8256 :         if (OidIsValid(dbid) &&
    1061        3154 :             hash_search(htab, (void *) &dbid, HASH_FIND, NULL) == NULL)
    1062           0 :             pgstat_drop_database(dbid);
    1063             :     }
    1064             : 
    1065             :     /* Clean up */
    1066        2368 :     hash_destroy(htab);
    1067             : 
    1068             :     /*
    1069             :      * Lookup our own database entry; if not found, nothing more to do.
    1070             :      */
    1071        2368 :     dbentry = (PgStat_StatDBEntry *) hash_search(pgStatDBHash,
    1072             :                                                  (void *) &MyDatabaseId,
    1073             :                                                  HASH_FIND, NULL);
    1074        2368 :     if (dbentry == NULL || dbentry->tables == NULL)
    1075         420 :         return;
    1076             : 
    1077             :     /*
    1078             :      * Similarly to above, make a list of all known relations in this DB.
    1079             :      */
    1080        1948 :     htab = pgstat_collect_oids(RelationRelationId, Anum_pg_class_oid);
    1081             : 
    1082             :     /*
    1083             :      * Initialize our messages table counter to zero
    1084             :      */
    1085        1948 :     msg.m_nentries = 0;
    1086             : 
    1087             :     /*
    1088             :      * Check for all tables listed in stats hashtable if they still exist.
    1089             :      */
    1090        1948 :     hash_seq_init(&hstat, dbentry->tables);
    1091      465040 :     while ((tabentry = (PgStat_StatTabEntry *) hash_seq_search(&hstat)) != NULL)
    1092             :     {
    1093      461144 :         Oid         tabid = tabentry->tableid;
    1094             : 
    1095      461144 :         CHECK_FOR_INTERRUPTS();
    1096             : 
    1097      461144 :         if (hash_search(htab, (void *) &tabid, HASH_FIND, NULL) != NULL)
    1098      368974 :             continue;
    1099             : 
    1100             :         /*
    1101             :          * Not there, so add this table's Oid to the message
    1102             :          */
    1103       92170 :         msg.m_tableid[msg.m_nentries++] = tabid;
    1104             : 
    1105             :         /*
    1106             :          * If the message is full, send it out and reinitialize to empty
    1107             :          */
    1108       92170 :         if (msg.m_nentries >= PGSTAT_NUM_TABPURGE)
    1109             :         {
    1110         166 :             len = offsetof(PgStat_MsgTabpurge, m_tableid[0])
    1111         166 :                 + msg.m_nentries * sizeof(Oid);
    1112             : 
    1113         166 :             pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_TABPURGE);
    1114         166 :             msg.m_databaseid = MyDatabaseId;
    1115         166 :             pgstat_send(&msg, len);
    1116             : 
    1117         166 :             msg.m_nentries = 0;
    1118             :         }
    1119             :     }
    1120             : 
    1121             :     /*
    1122             :      * Send the rest
    1123             :      */
    1124        1948 :     if (msg.m_nentries > 0)
    1125             :     {
    1126         732 :         len = offsetof(PgStat_MsgTabpurge, m_tableid[0])
    1127         732 :             + msg.m_nentries * sizeof(Oid);
    1128             : 
    1129         732 :         pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_TABPURGE);
    1130         732 :         msg.m_databaseid = MyDatabaseId;
    1131         732 :         pgstat_send(&msg, len);
    1132             :     }
    1133             : 
    1134             :     /* Clean up */
    1135        1948 :     hash_destroy(htab);
    1136             : 
    1137             :     /*
    1138             :      * Now repeat the above steps for functions.  However, we needn't bother
    1139             :      * in the common case where no function stats are being collected.
    1140             :      */
    1141        3896 :     if (dbentry->functions != NULL &&
    1142        1948 :         hash_get_num_entries(dbentry->functions) > 0)
    1143             :     {
    1144           0 :         htab = pgstat_collect_oids(ProcedureRelationId, Anum_pg_proc_oid);
    1145             : 
    1146           0 :         pgstat_setheader(&f_msg.m_hdr, PGSTAT_MTYPE_FUNCPURGE);
    1147           0 :         f_msg.m_databaseid = MyDatabaseId;
    1148           0 :         f_msg.m_nentries = 0;
    1149             : 
    1150           0 :         hash_seq_init(&hstat, dbentry->functions);
    1151           0 :         while ((funcentry = (PgStat_StatFuncEntry *) hash_seq_search(&hstat)) != NULL)
    1152             :         {
    1153           0 :             Oid         funcid = funcentry->functionid;
    1154             : 
    1155           0 :             CHECK_FOR_INTERRUPTS();
    1156             : 
    1157           0 :             if (hash_search(htab, (void *) &funcid, HASH_FIND, NULL) != NULL)
    1158           0 :                 continue;
    1159             : 
    1160             :             /*
    1161             :              * Not there, so add this function's Oid to the message
    1162             :              */
    1163           0 :             f_msg.m_functionid[f_msg.m_nentries++] = funcid;
    1164             : 
    1165             :             /*
    1166             :              * If the message is full, send it out and reinitialize to empty
    1167             :              */
    1168           0 :             if (f_msg.m_nentries >= PGSTAT_NUM_FUNCPURGE)
    1169             :             {
    1170           0 :                 len = offsetof(PgStat_MsgFuncpurge, m_functionid[0])
    1171           0 :                     + f_msg.m_nentries * sizeof(Oid);
    1172             : 
    1173           0 :                 pgstat_send(&f_msg, len);
    1174             : 
    1175           0 :                 f_msg.m_nentries = 0;
    1176             :             }
    1177             :         }
    1178             : 
    1179             :         /*
    1180             :          * Send the rest
    1181             :          */
    1182           0 :         if (f_msg.m_nentries > 0)
    1183             :         {
    1184           0 :             len = offsetof(PgStat_MsgFuncpurge, m_functionid[0])
    1185           0 :                 + f_msg.m_nentries * sizeof(Oid);
    1186             : 
    1187           0 :             pgstat_send(&f_msg, len);
    1188             :         }
    1189             : 
    1190           0 :         hash_destroy(htab);
    1191             :     }
    1192             : }
    1193             : 
    1194             : 
    1195             : /* ----------
    1196             :  * pgstat_collect_oids() -
    1197             :  *
    1198             :  *  Collect the OIDs of all objects listed in the specified system catalog
    1199             :  *  into a temporary hash table.  Caller should hash_destroy the result
    1200             :  *  when done with it.  (However, we make the table in CurrentMemoryContext
    1201             :  *  so that it will be freed properly in event of an error.)
    1202             :  * ----------
    1203             :  */
    1204             : static HTAB *
    1205        4316 : pgstat_collect_oids(Oid catalogid, AttrNumber anum_oid)
    1206             : {
    1207             :     HTAB       *htab;
    1208             :     HASHCTL     hash_ctl;
    1209             :     Relation    rel;
    1210             :     TableScanDesc scan;
    1211             :     HeapTuple   tup;
    1212             :     Snapshot    snapshot;
    1213             : 
    1214        4316 :     memset(&hash_ctl, 0, sizeof(hash_ctl));
    1215        4316 :     hash_ctl.keysize = sizeof(Oid);
    1216        4316 :     hash_ctl.entrysize = sizeof(Oid);
    1217        4316 :     hash_ctl.hcxt = CurrentMemoryContext;
    1218        4316 :     htab = hash_create("Temporary table of OIDs",
    1219             :                        PGSTAT_TAB_HASH_SIZE,
    1220             :                        &hash_ctl,
    1221             :                        HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
    1222             : 
    1223        4316 :     rel = table_open(catalogid, AccessShareLock);
    1224        4316 :     snapshot = RegisterSnapshot(GetLatestSnapshot());
    1225        4316 :     scan = table_beginscan(rel, snapshot, 0, NULL);
    1226      936434 :     while ((tup = heap_getnext(scan, ForwardScanDirection)) != NULL)
    1227             :     {
    1228             :         Oid         thisoid;
    1229             :         bool        isnull;
    1230             : 
    1231      927802 :         thisoid = heap_getattr(tup, anum_oid, RelationGetDescr(rel), &isnull);
    1232             :         Assert(!isnull);
    1233             : 
    1234      927802 :         CHECK_FOR_INTERRUPTS();
    1235             : 
    1236      927802 :         (void) hash_search(htab, (void *) &thisoid, HASH_ENTER, NULL);
    1237             :     }
    1238        4316 :     table_endscan(scan);
    1239        4316 :     UnregisterSnapshot(snapshot);
    1240        4316 :     table_close(rel, AccessShareLock);
    1241             : 
    1242        4316 :     return htab;
    1243             : }
    1244             : 
    1245             : 
    1246             : /* ----------
    1247             :  * pgstat_drop_database() -
    1248             :  *
    1249             :  *  Tell the collector that we just dropped a database.
    1250             :  *  (If the message gets lost, we will still clean the dead DB eventually
    1251             :  *  via future invocations of pgstat_vacuum_stat().)
    1252             :  * ----------
    1253             :  */
    1254             : void
    1255          16 : pgstat_drop_database(Oid databaseid)
    1256             : {
    1257             :     PgStat_MsgDropdb msg;
    1258             : 
    1259          16 :     if (pgStatSock == PGINVALID_SOCKET)
    1260           0 :         return;
    1261             : 
    1262          16 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_DROPDB);
    1263          16 :     msg.m_databaseid = databaseid;
    1264          16 :     pgstat_send(&msg, sizeof(msg));
    1265             : }
    1266             : 
    1267             : 
    1268             : /* ----------
    1269             :  * pgstat_drop_relation() -
    1270             :  *
    1271             :  *  Tell the collector that we just dropped a relation.
    1272             :  *  (If the message gets lost, we will still clean the dead entry eventually
    1273             :  *  via future invocations of pgstat_vacuum_stat().)
    1274             :  *
    1275             :  *  Currently not used for lack of any good place to call it; we rely
    1276             :  *  entirely on pgstat_vacuum_stat() to clean out stats for dead rels.
    1277             :  * ----------
    1278             :  */
    1279             : #ifdef NOT_USED
    1280             : void
    1281             : pgstat_drop_relation(Oid relid)
    1282             : {
    1283             :     PgStat_MsgTabpurge msg;
    1284             :     int         len;
    1285             : 
    1286             :     if (pgStatSock == PGINVALID_SOCKET)
    1287             :         return;
    1288             : 
    1289             :     msg.m_tableid[0] = relid;
    1290             :     msg.m_nentries = 1;
    1291             : 
    1292             :     len = offsetof(PgStat_MsgTabpurge, m_tableid[0]) + sizeof(Oid);
    1293             : 
    1294             :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_TABPURGE);
    1295             :     msg.m_databaseid = MyDatabaseId;
    1296             :     pgstat_send(&msg, len);
    1297             : }
    1298             : #endif                          /* NOT_USED */
    1299             : 
    1300             : 
    1301             : /* ----------
    1302             :  * pgstat_reset_counters() -
    1303             :  *
    1304             :  *  Tell the statistics collector to reset counters for our database.
    1305             :  *
    1306             :  *  Permission checking for this function is managed through the normal
    1307             :  *  GRANT system.
    1308             :  * ----------
    1309             :  */
    1310             : void
    1311           0 : pgstat_reset_counters(void)
    1312             : {
    1313             :     PgStat_MsgResetcounter msg;
    1314             : 
    1315           0 :     if (pgStatSock == PGINVALID_SOCKET)
    1316           0 :         return;
    1317             : 
    1318           0 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_RESETCOUNTER);
    1319           0 :     msg.m_databaseid = MyDatabaseId;
    1320           0 :     pgstat_send(&msg, sizeof(msg));
    1321             : }
    1322             : 
    1323             : /* ----------
    1324             :  * pgstat_reset_shared_counters() -
    1325             :  *
    1326             :  *  Tell the statistics collector to reset cluster-wide shared counters.
    1327             :  *
    1328             :  *  Permission checking for this function is managed through the normal
    1329             :  *  GRANT system.
    1330             :  * ----------
    1331             :  */
    1332             : void
    1333           0 : pgstat_reset_shared_counters(const char *target)
    1334             : {
    1335             :     PgStat_MsgResetsharedcounter msg;
    1336             : 
    1337           0 :     if (pgStatSock == PGINVALID_SOCKET)
    1338           0 :         return;
    1339             : 
    1340           0 :     if (strcmp(target, "archiver") == 0)
    1341           0 :         msg.m_resettarget = RESET_ARCHIVER;
    1342           0 :     else if (strcmp(target, "bgwriter") == 0)
    1343           0 :         msg.m_resettarget = RESET_BGWRITER;
    1344             :     else
    1345           0 :         ereport(ERROR,
    1346             :                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
    1347             :                  errmsg("unrecognized reset target: \"%s\"", target),
    1348             :                  errhint("Target must be \"archiver\" or \"bgwriter\".")));
    1349             : 
    1350           0 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_RESETSHAREDCOUNTER);
    1351           0 :     pgstat_send(&msg, sizeof(msg));
    1352             : }
    1353             : 
    1354             : /* ----------
    1355             :  * pgstat_reset_single_counter() -
    1356             :  *
    1357             :  *  Tell the statistics collector to reset a single counter.
    1358             :  *
    1359             :  *  Permission checking for this function is managed through the normal
    1360             :  *  GRANT system.
    1361             :  * ----------
    1362             :  */
    1363             : void
    1364           0 : pgstat_reset_single_counter(Oid objoid, PgStat_Single_Reset_Type type)
    1365             : {
    1366             :     PgStat_MsgResetsinglecounter msg;
    1367             : 
    1368           0 :     if (pgStatSock == PGINVALID_SOCKET)
    1369           0 :         return;
    1370             : 
    1371           0 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_RESETSINGLECOUNTER);
    1372           0 :     msg.m_databaseid = MyDatabaseId;
    1373           0 :     msg.m_resettype = type;
    1374           0 :     msg.m_objectid = objoid;
    1375             : 
    1376           0 :     pgstat_send(&msg, sizeof(msg));
    1377             : }
    1378             : 
    1379             : /* ----------
    1380             :  * pgstat_report_autovac() -
    1381             :  *
    1382             :  *  Called from autovacuum.c to report startup of an autovacuum process.
    1383             :  *  We are called before InitPostgres is done, so can't rely on MyDatabaseId;
    1384             :  *  the db OID must be passed in, instead.
    1385             :  * ----------
    1386             :  */
    1387             : void
    1388          64 : pgstat_report_autovac(Oid dboid)
    1389             : {
    1390             :     PgStat_MsgAutovacStart msg;
    1391             : 
    1392          64 :     if (pgStatSock == PGINVALID_SOCKET)
    1393           0 :         return;
    1394             : 
    1395          64 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_AUTOVAC_START);
    1396          64 :     msg.m_databaseid = dboid;
    1397          64 :     msg.m_start_time = GetCurrentTimestamp();
    1398             : 
    1399          64 :     pgstat_send(&msg, sizeof(msg));
    1400             : }
    1401             : 
    1402             : 
    1403             : /* ---------
    1404             :  * pgstat_report_vacuum() -
    1405             :  *
    1406             :  *  Tell the collector about the table we just vacuumed.
    1407             :  * ---------
    1408             :  */
    1409             : void
    1410       41688 : pgstat_report_vacuum(Oid tableoid, bool shared,
    1411             :                      PgStat_Counter livetuples, PgStat_Counter deadtuples)
    1412             : {
    1413             :     PgStat_MsgVacuum msg;
    1414             : 
    1415       41688 :     if (pgStatSock == PGINVALID_SOCKET || !pgstat_track_counts)
    1416       37120 :         return;
    1417             : 
    1418        4568 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_VACUUM);
    1419        4568 :     msg.m_databaseid = shared ? InvalidOid : MyDatabaseId;
    1420        4568 :     msg.m_tableoid = tableoid;
    1421        4568 :     msg.m_autovacuum = IsAutoVacuumWorkerProcess();
    1422        4568 :     msg.m_vacuumtime = GetCurrentTimestamp();
    1423        4568 :     msg.m_live_tuples = livetuples;
    1424        4568 :     msg.m_dead_tuples = deadtuples;
    1425        4568 :     pgstat_send(&msg, sizeof(msg));
    1426             : }
    1427             : 
    1428             : /* --------
    1429             :  * pgstat_report_analyze() -
    1430             :  *
    1431             :  *  Tell the collector about the table we just analyzed.
    1432             :  *
    1433             :  * Caller must provide new live- and dead-tuples estimates, as well as a
    1434             :  * flag indicating whether to reset the changes_since_analyze counter.
    1435             :  * --------
    1436             :  */
    1437             : void
    1438       31720 : pgstat_report_analyze(Relation rel,
    1439             :                       PgStat_Counter livetuples, PgStat_Counter deadtuples,
    1440             :                       bool resetcounter)
    1441             : {
    1442             :     PgStat_MsgAnalyze msg;
    1443             : 
    1444       31720 :     if (pgStatSock == PGINVALID_SOCKET || !pgstat_track_counts)
    1445       22080 :         return;
    1446             : 
    1447             :     /*
    1448             :      * Unlike VACUUM, ANALYZE might be running inside a transaction that has
    1449             :      * already inserted and/or deleted rows in the target table. ANALYZE will
    1450             :      * have counted such rows as live or dead respectively. Because we will
    1451             :      * report our counts of such rows at transaction end, we should subtract
    1452             :      * off these counts from what we send to the collector now, else they'll
    1453             :      * be double-counted after commit.  (This approach also ensures that the
    1454             :      * collector ends up with the right numbers if we abort instead of
    1455             :      * committing.)
    1456             :      */
    1457        9640 :     if (rel->pgstat_info != NULL)
    1458             :     {
    1459             :         PgStat_TableXactStatus *trans;
    1460             : 
    1461        9668 :         for (trans = rel->pgstat_info->trans; trans; trans = trans->upper)
    1462             :         {
    1463          60 :             livetuples -= trans->tuples_inserted - trans->tuples_deleted;
    1464          60 :             deadtuples -= trans->tuples_updated + trans->tuples_deleted;
    1465             :         }
    1466             :         /* count stuff inserted by already-aborted subxacts, too */
    1467        9608 :         deadtuples -= rel->pgstat_info->t_counts.t_delta_dead_tuples;
    1468             :         /* Since ANALYZE's counts are estimates, we could have underflowed */
    1469        9608 :         livetuples = Max(livetuples, 0);
    1470        9608 :         deadtuples = Max(deadtuples, 0);
    1471             :     }
    1472             : 
    1473        9640 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_ANALYZE);
    1474        9640 :     msg.m_databaseid = rel->rd_rel->relisshared ? InvalidOid : MyDatabaseId;
    1475        9640 :     msg.m_tableoid = RelationGetRelid(rel);
    1476        9640 :     msg.m_autovacuum = IsAutoVacuumWorkerProcess();
    1477        9640 :     msg.m_resetcounter = resetcounter;
    1478        9640 :     msg.m_analyzetime = GetCurrentTimestamp();
    1479        9640 :     msg.m_live_tuples = livetuples;
    1480        9640 :     msg.m_dead_tuples = deadtuples;
    1481        9640 :     pgstat_send(&msg, sizeof(msg));
    1482             : }
    1483             : 
    1484             : /* --------
    1485             :  * pgstat_report_recovery_conflict() -
    1486             :  *
    1487             :  *  Tell the collector about a Hot Standby recovery conflict.
    1488             :  * --------
    1489             :  */
    1490             : void
    1491           0 : pgstat_report_recovery_conflict(int reason)
    1492             : {
    1493             :     PgStat_MsgRecoveryConflict msg;
    1494             : 
    1495           0 :     if (pgStatSock == PGINVALID_SOCKET || !pgstat_track_counts)
    1496           0 :         return;
    1497             : 
    1498           0 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_RECOVERYCONFLICT);
    1499           0 :     msg.m_databaseid = MyDatabaseId;
    1500           0 :     msg.m_reason = reason;
    1501           0 :     pgstat_send(&msg, sizeof(msg));
    1502             : }
    1503             : 
    1504             : /* --------
    1505             :  * pgstat_report_deadlock() -
    1506             :  *
    1507             :  *  Tell the collector about a deadlock detected.
    1508             :  * --------
    1509             :  */
    1510             : void
    1511           4 : pgstat_report_deadlock(void)
    1512             : {
    1513             :     PgStat_MsgDeadlock msg;
    1514             : 
    1515           4 :     if (pgStatSock == PGINVALID_SOCKET || !pgstat_track_counts)
    1516           0 :         return;
    1517             : 
    1518           4 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_DEADLOCK);
    1519           4 :     msg.m_databaseid = MyDatabaseId;
    1520           4 :     pgstat_send(&msg, sizeof(msg));
    1521             : }
    1522             : 
    1523             : 
    1524             : 
    1525             : /* --------
    1526             :  * pgstat_report_checksum_failures_in_db() -
    1527             :  *
    1528             :  *  Tell the collector about one or more checksum failures.
    1529             :  * --------
    1530             :  */
    1531             : void
    1532           4 : pgstat_report_checksum_failures_in_db(Oid dboid, int failurecount)
    1533             : {
    1534             :     PgStat_MsgChecksumFailure msg;
    1535             : 
    1536           4 :     if (pgStatSock == PGINVALID_SOCKET || !pgstat_track_counts)
    1537           0 :         return;
    1538             : 
    1539           4 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_CHECKSUMFAILURE);
    1540           4 :     msg.m_databaseid = dboid;
    1541           4 :     msg.m_failurecount = failurecount;
    1542           4 :     msg.m_failure_time = GetCurrentTimestamp();
    1543             : 
    1544           4 :     pgstat_send(&msg, sizeof(msg));
    1545             : }
    1546             : 
    1547             : /* --------
    1548             :  * pgstat_report_checksum_failure() -
    1549             :  *
    1550             :  *  Tell the collector about a checksum failure.
    1551             :  * --------
    1552             :  */
    1553             : void
    1554           0 : pgstat_report_checksum_failure(void)
    1555             : {
    1556           0 :     pgstat_report_checksum_failures_in_db(MyDatabaseId, 1);
    1557           0 : }
    1558             : 
    1559             : /* --------
    1560             :  * pgstat_report_tempfile() -
    1561             :  *
    1562             :  *  Tell the collector about a temporary file.
    1563             :  * --------
    1564             :  */
    1565             : void
    1566        3188 : pgstat_report_tempfile(size_t filesize)
    1567             : {
    1568             :     PgStat_MsgTempFile msg;
    1569             : 
    1570        3188 :     if (pgStatSock == PGINVALID_SOCKET || !pgstat_track_counts)
    1571           0 :         return;
    1572             : 
    1573        3188 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_TEMPFILE);
    1574        3188 :     msg.m_databaseid = MyDatabaseId;
    1575        3188 :     msg.m_filesize = filesize;
    1576        3188 :     pgstat_send(&msg, sizeof(msg));
    1577             : }
    1578             : 
    1579             : 
    1580             : /* ----------
    1581             :  * pgstat_ping() -
    1582             :  *
    1583             :  *  Send some junk data to the collector to increase traffic.
    1584             :  * ----------
    1585             :  */
    1586             : void
    1587           0 : pgstat_ping(void)
    1588             : {
    1589             :     PgStat_MsgDummy msg;
    1590             : 
    1591           0 :     if (pgStatSock == PGINVALID_SOCKET)
    1592           0 :         return;
    1593             : 
    1594           0 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_DUMMY);
    1595           0 :     pgstat_send(&msg, sizeof(msg));
    1596             : }
    1597             : 
    1598             : /* ----------
    1599             :  * pgstat_send_inquiry() -
    1600             :  *
    1601             :  *  Notify collector that we need fresh data.
    1602             :  * ----------
    1603             :  */
    1604             : static void
    1605        1032 : pgstat_send_inquiry(TimestampTz clock_time, TimestampTz cutoff_time, Oid databaseid)
    1606             : {
    1607             :     PgStat_MsgInquiry msg;
    1608             : 
    1609        1032 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_INQUIRY);
    1610        1032 :     msg.clock_time = clock_time;
    1611        1032 :     msg.cutoff_time = cutoff_time;
    1612        1032 :     msg.databaseid = databaseid;
    1613        1032 :     pgstat_send(&msg, sizeof(msg));
    1614        1032 : }
    1615             : 
    1616             : 
    1617             : /*
    1618             :  * Initialize function call usage data.
    1619             :  * Called by the executor before invoking a function.
    1620             :  */
    1621             : void
    1622    14382592 : pgstat_init_function_usage(FunctionCallInfo fcinfo,
    1623             :                            PgStat_FunctionCallUsage *fcu)
    1624             : {
    1625             :     PgStat_BackendFunctionEntry *htabent;
    1626             :     bool        found;
    1627             : 
    1628    14382592 :     if (pgstat_track_functions <= fcinfo->flinfo->fn_stats)
    1629             :     {
    1630             :         /* stats not wanted */
    1631    14382592 :         fcu->fs = NULL;
    1632    14382592 :         return;
    1633             :     }
    1634             : 
    1635           0 :     if (!pgStatFunctions)
    1636             :     {
    1637             :         /* First time through - initialize function stat table */
    1638             :         HASHCTL     hash_ctl;
    1639             : 
    1640           0 :         memset(&hash_ctl, 0, sizeof(hash_ctl));
    1641           0 :         hash_ctl.keysize = sizeof(Oid);
    1642           0 :         hash_ctl.entrysize = sizeof(PgStat_BackendFunctionEntry);
    1643           0 :         pgStatFunctions = hash_create("Function stat entries",
    1644             :                                       PGSTAT_FUNCTION_HASH_SIZE,
    1645             :                                       &hash_ctl,
    1646             :                                       HASH_ELEM | HASH_BLOBS);
    1647             :     }
    1648             : 
    1649             :     /* Get the stats entry for this function, create if necessary */
    1650           0 :     htabent = hash_search(pgStatFunctions, &fcinfo->flinfo->fn_oid,
    1651             :                           HASH_ENTER, &found);
    1652           0 :     if (!found)
    1653           0 :         MemSet(&htabent->f_counts, 0, sizeof(PgStat_FunctionCounts));
    1654             : 
    1655           0 :     fcu->fs = &htabent->f_counts;
    1656             : 
    1657             :     /* save stats for this function, later used to compensate for recursion */
    1658           0 :     fcu->save_f_total_time = htabent->f_counts.f_total_time;
    1659             : 
    1660             :     /* save current backend-wide total time */
    1661           0 :     fcu->save_total = total_func_time;
    1662             : 
    1663             :     /* get clock time as of function start */
    1664           0 :     INSTR_TIME_SET_CURRENT(fcu->f_start);
    1665             : }
    1666             : 
    1667             : /*
    1668             :  * find_funcstat_entry - find any existing PgStat_BackendFunctionEntry entry
    1669             :  *      for specified function
    1670             :  *
    1671             :  * If no entry, return NULL, don't create a new one
    1672             :  */
    1673             : PgStat_BackendFunctionEntry *
    1674           0 : find_funcstat_entry(Oid func_id)
    1675             : {
    1676           0 :     if (pgStatFunctions == NULL)
    1677           0 :         return NULL;
    1678             : 
    1679           0 :     return (PgStat_BackendFunctionEntry *) hash_search(pgStatFunctions,
    1680             :                                                        (void *) &func_id,
    1681             :                                                        HASH_FIND, NULL);
    1682             : }
    1683             : 
    1684             : /*
    1685             :  * Calculate function call usage and update stat counters.
    1686             :  * Called by the executor after invoking a function.
    1687             :  *
    1688             :  * In the case of a set-returning function that runs in value-per-call mode,
    1689             :  * we will see multiple pgstat_init_function_usage/pgstat_end_function_usage
    1690             :  * calls for what the user considers a single call of the function.  The
    1691             :  * finalize flag should be TRUE on the last call.
    1692             :  */
    1693             : void
    1694    14381056 : pgstat_end_function_usage(PgStat_FunctionCallUsage *fcu, bool finalize)
    1695             : {
    1696    14381056 :     PgStat_FunctionCounts *fs = fcu->fs;
    1697             :     instr_time  f_total;
    1698             :     instr_time  f_others;
    1699             :     instr_time  f_self;
    1700             : 
    1701             :     /* stats not wanted? */
    1702    14381056 :     if (fs == NULL)
    1703    14381056 :         return;
    1704             : 
    1705             :     /* total elapsed time in this function call */
    1706           0 :     INSTR_TIME_SET_CURRENT(f_total);
    1707           0 :     INSTR_TIME_SUBTRACT(f_total, fcu->f_start);
    1708             : 
    1709             :     /* self usage: elapsed minus anything already charged to other calls */
    1710           0 :     f_others = total_func_time;
    1711           0 :     INSTR_TIME_SUBTRACT(f_others, fcu->save_total);
    1712           0 :     f_self = f_total;
    1713           0 :     INSTR_TIME_SUBTRACT(f_self, f_others);
    1714             : 
    1715             :     /* update backend-wide total time */
    1716           0 :     INSTR_TIME_ADD(total_func_time, f_self);
    1717             : 
    1718             :     /*
    1719             :      * Compute the new f_total_time as the total elapsed time added to the
    1720             :      * pre-call value of f_total_time.  This is necessary to avoid
    1721             :      * double-counting any time taken by recursive calls of myself.  (We do
    1722             :      * not need any similar kluge for self time, since that already excludes
    1723             :      * any recursive calls.)
    1724             :      */
    1725           0 :     INSTR_TIME_ADD(f_total, fcu->save_f_total_time);
    1726             : 
    1727             :     /* update counters in function stats table */
    1728           0 :     if (finalize)
    1729           0 :         fs->f_numcalls++;
    1730           0 :     fs->f_total_time = f_total;
    1731           0 :     INSTR_TIME_ADD(fs->f_self_time, f_self);
    1732             : 
    1733             :     /* indicate that we have something to send */
    1734           0 :     have_function_stats = true;
    1735             : }
    1736             : 
    1737             : 
    1738             : /* ----------
    1739             :  * pgstat_initstats() -
    1740             :  *
    1741             :  *  Initialize a relcache entry to count access statistics.
    1742             :  *  Called whenever a relation is opened.
    1743             :  *
    1744             :  *  We assume that a relcache entry's pgstat_info field is zeroed by
    1745             :  *  relcache.c when the relcache entry is made; thereafter it is long-lived
    1746             :  *  data.  We can avoid repeated searches of the TabStatus arrays when the
    1747             :  *  same relation is touched repeatedly within a transaction.
    1748             :  * ----------
    1749             :  */
    1750             : void
    1751    27069104 : pgstat_initstats(Relation rel)
    1752             : {
    1753    27069104 :     Oid         rel_id = rel->rd_id;
    1754    27069104 :     char        relkind = rel->rd_rel->relkind;
    1755             : 
    1756             :     /* We only count stats for things that have storage */
    1757    27467074 :     if (!(relkind == RELKIND_RELATION ||
    1758    14821206 :           relkind == RELKIND_MATVIEW ||
    1759      548138 :           relkind == RELKIND_INDEX ||
    1760             :           relkind == RELKIND_TOASTVALUE ||
    1761             :           relkind == RELKIND_SEQUENCE))
    1762             :     {
    1763      332414 :         rel->pgstat_info = NULL;
    1764      332414 :         return;
    1765             :     }
    1766             : 
    1767    26736690 :     if (pgStatSock == PGINVALID_SOCKET || !pgstat_track_counts)
    1768             :     {
    1769             :         /* We're not counting at all */
    1770    12346584 :         rel->pgstat_info = NULL;
    1771    12346584 :         return;
    1772             :     }
    1773             : 
    1774             :     /*
    1775             :      * If we already set up this relation in the current transaction, nothing
    1776             :      * to do.
    1777             :      */
    1778    28167808 :     if (rel->pgstat_info != NULL &&
    1779    13777702 :         rel->pgstat_info->t_id == rel_id)
    1780    13645168 :         return;
    1781             : 
    1782             :     /* Else find or make the PgStat_TableStatus entry, and update link */
    1783      744938 :     rel->pgstat_info = get_tabstat_entry(rel_id, rel->rd_rel->relisshared);
    1784             : }
    1785             : 
    1786             : /*
    1787             :  * get_tabstat_entry - find or create a PgStat_TableStatus entry for rel
    1788             :  */
    1789             : static PgStat_TableStatus *
    1790      745078 : get_tabstat_entry(Oid rel_id, bool isshared)
    1791             : {
    1792             :     TabStatHashEntry *hash_entry;
    1793             :     PgStat_TableStatus *entry;
    1794             :     TabStatusArray *tsa;
    1795             :     bool        found;
    1796             : 
    1797             :     /*
    1798             :      * Create hash table if we don't have it already.
    1799             :      */
    1800      745078 :     if (pgStatTabHash == NULL)
    1801             :     {
    1802             :         HASHCTL     ctl;
    1803             : 
    1804       16466 :         memset(&ctl, 0, sizeof(ctl));
    1805       16466 :         ctl.keysize = sizeof(Oid);
    1806       16466 :         ctl.entrysize = sizeof(TabStatHashEntry);
    1807             : 
    1808       16466 :         pgStatTabHash = hash_create("pgstat TabStatusArray lookup hash table",
    1809             :                                     TABSTAT_QUANTUM,
    1810             :                                     &ctl,
    1811             :                                     HASH_ELEM | HASH_BLOBS);
    1812             :     }
    1813             : 
    1814             :     /*
    1815             :      * Find an entry or create a new one.
    1816             :      */
    1817      745078 :     hash_entry = hash_search(pgStatTabHash, &rel_id, HASH_ENTER, &found);
    1818      745078 :     if (!found)
    1819             :     {
    1820             :         /* initialize new entry with null pointer */
    1821      665180 :         hash_entry->tsa_entry = NULL;
    1822             :     }
    1823             : 
    1824             :     /*
    1825             :      * If entry is already valid, we're done.
    1826             :      */
    1827      745078 :     if (hash_entry->tsa_entry)
    1828       79898 :         return hash_entry->tsa_entry;
    1829             : 
    1830             :     /*
    1831             :      * Locate the first pgStatTabList entry with free space, making a new list
    1832             :      * entry if needed.  Note that we could get an OOM failure here, but if so
    1833             :      * we have left the hashtable and the list in a consistent state.
    1834             :      */
    1835      665180 :     if (pgStatTabList == NULL)
    1836             :     {
    1837             :         /* Set up first pgStatTabList entry */
    1838        9130 :         pgStatTabList = (TabStatusArray *)
    1839        9130 :             MemoryContextAllocZero(TopMemoryContext,
    1840             :                                    sizeof(TabStatusArray));
    1841             :     }
    1842             : 
    1843      665180 :     tsa = pgStatTabList;
    1844     1439072 :     while (tsa->tsa_used >= TABSTAT_QUANTUM)
    1845             :     {
    1846      108712 :         if (tsa->tsa_next == NULL)
    1847        1594 :             tsa->tsa_next = (TabStatusArray *)
    1848        1594 :                 MemoryContextAllocZero(TopMemoryContext,
    1849             :                                        sizeof(TabStatusArray));
    1850      108712 :         tsa = tsa->tsa_next;
    1851             :     }
    1852             : 
    1853             :     /*
    1854             :      * Allocate a PgStat_TableStatus entry within this list entry.  We assume
    1855             :      * the entry was already zeroed, either at creation or after last use.
    1856             :      */
    1857      665180 :     entry = &tsa->tsa_entries[tsa->tsa_used++];
    1858      665180 :     entry->t_id = rel_id;
    1859      665180 :     entry->t_shared = isshared;
    1860             : 
    1861             :     /*
    1862             :      * Now we can fill the entry in pgStatTabHash.
    1863             :      */
    1864      665180 :     hash_entry->tsa_entry = entry;
    1865             : 
    1866      665180 :     return entry;
    1867             : }
    1868             : 
    1869             : /*
    1870             :  * find_tabstat_entry - find any existing PgStat_TableStatus entry for rel
    1871             :  *
    1872             :  * If no entry, return NULL, don't create a new one
    1873             :  *
    1874             :  * Note: if we got an error in the most recent execution of pgstat_report_stat,
    1875             :  * it's possible that an entry exists but there's no hashtable entry for it.
    1876             :  * That's okay, we'll treat this case as "doesn't exist".
    1877             :  */
    1878             : PgStat_TableStatus *
    1879           0 : find_tabstat_entry(Oid rel_id)
    1880             : {
    1881             :     TabStatHashEntry *hash_entry;
    1882             : 
    1883             :     /* If hashtable doesn't exist, there are no entries at all */
    1884           0 :     if (!pgStatTabHash)
    1885           0 :         return NULL;
    1886             : 
    1887           0 :     hash_entry = hash_search(pgStatTabHash, &rel_id, HASH_FIND, NULL);
    1888           0 :     if (!hash_entry)
    1889           0 :         return NULL;
    1890             : 
    1891             :     /* Note that this step could also return NULL, but that's correct */
    1892           0 :     return hash_entry->tsa_entry;
    1893             : }
    1894             : 
    1895             : /*
    1896             :  * get_tabstat_stack_level - add a new (sub)transaction stack entry if needed
    1897             :  */
    1898             : static PgStat_SubXactStatus *
    1899      253618 : get_tabstat_stack_level(int nest_level)
    1900             : {
    1901             :     PgStat_SubXactStatus *xact_state;
    1902             : 
    1903      253618 :     xact_state = pgStatXactStack;
    1904      253618 :     if (xact_state == NULL || xact_state->nest_level != nest_level)
    1905             :     {
    1906       89616 :         xact_state = (PgStat_SubXactStatus *)
    1907       89616 :             MemoryContextAlloc(TopTransactionContext,
    1908             :                                sizeof(PgStat_SubXactStatus));
    1909       89616 :         xact_state->nest_level = nest_level;
    1910       89616 :         xact_state->prev = pgStatXactStack;
    1911       89616 :         xact_state->first = NULL;
    1912       89616 :         pgStatXactStack = xact_state;
    1913             :     }
    1914      253618 :     return xact_state;
    1915             : }
    1916             : 
    1917             : /*
    1918             :  * add_tabstat_xact_level - add a new (sub)transaction state record
    1919             :  */
    1920             : static void
    1921      252980 : add_tabstat_xact_level(PgStat_TableStatus *pgstat_info, int nest_level)
    1922             : {
    1923             :     PgStat_SubXactStatus *xact_state;
    1924             :     PgStat_TableXactStatus *trans;
    1925             : 
    1926             :     /*
    1927             :      * If this is the first rel to be modified at the current nest level, we
    1928             :      * first have to push a transaction stack entry.
    1929             :      */
    1930      252980 :     xact_state = get_tabstat_stack_level(nest_level);
    1931             : 
    1932             :     /* Now make a per-table stack entry */
    1933      252980 :     trans = (PgStat_TableXactStatus *)
    1934      252980 :         MemoryContextAllocZero(TopTransactionContext,
    1935             :                                sizeof(PgStat_TableXactStatus));
    1936      252980 :     trans->nest_level = nest_level;
    1937      252980 :     trans->upper = pgstat_info->trans;
    1938      252980 :     trans->parent = pgstat_info;
    1939      252980 :     trans->next = xact_state->first;
    1940      252980 :     xact_state->first = trans;
    1941      252980 :     pgstat_info->trans = trans;
    1942      252980 : }
    1943             : 
    1944             : /*
    1945             :  * pgstat_count_heap_insert - count a tuple insertion of n tuples
    1946             :  */
    1947             : void
    1948    17201610 : pgstat_count_heap_insert(Relation rel, PgStat_Counter n)
    1949             : {
    1950    17201610 :     PgStat_TableStatus *pgstat_info = rel->pgstat_info;
    1951             : 
    1952    17201610 :     if (pgstat_info != NULL)
    1953             :     {
    1954             :         /* We have to log the effect at the proper transactional level */
    1955     9895050 :         int         nest_level = GetCurrentTransactionNestLevel();
    1956             : 
    1957    19625064 :         if (pgstat_info->trans == NULL ||
    1958     9730014 :             pgstat_info->trans->nest_level != nest_level)
    1959      168214 :             add_tabstat_xact_level(pgstat_info, nest_level);
    1960             : 
    1961     9895050 :         pgstat_info->trans->tuples_inserted += n;
    1962             :     }
    1963    17201610 : }
    1964             : 
    1965             : /*
    1966             :  * pgstat_count_heap_update - count a tuple update
    1967             :  */
    1968             : void
    1969      306396 : pgstat_count_heap_update(Relation rel, bool hot)
    1970             : {
    1971      306396 :     PgStat_TableStatus *pgstat_info = rel->pgstat_info;
    1972             : 
    1973      306396 :     if (pgstat_info != NULL)
    1974             :     {
    1975             :         /* We have to log the effect at the proper transactional level */
    1976      176476 :         int         nest_level = GetCurrentTransactionNestLevel();
    1977             : 
    1978      327768 :         if (pgstat_info->trans == NULL ||
    1979      151292 :             pgstat_info->trans->nest_level != nest_level)
    1980       25244 :             add_tabstat_xact_level(pgstat_info, nest_level);
    1981             : 
    1982      176476 :         pgstat_info->trans->tuples_updated++;
    1983             : 
    1984             :         /* t_tuples_hot_updated is nontransactional, so just advance it */
    1985      176476 :         if (hot)
    1986      114150 :             pgstat_info->t_counts.t_tuples_hot_updated++;
    1987             :     }
    1988      306396 : }
    1989             : 
    1990             : /*
    1991             :  * pgstat_count_heap_delete - count a tuple deletion
    1992             :  */
    1993             : void
    1994     1549694 : pgstat_count_heap_delete(Relation rel)
    1995             : {
    1996     1549694 :     PgStat_TableStatus *pgstat_info = rel->pgstat_info;
    1997             : 
    1998     1549694 :     if (pgstat_info != NULL)
    1999             :     {
    2000             :         /* We have to log the effect at the proper transactional level */
    2001     1521854 :         int         nest_level = GetCurrentTransactionNestLevel();
    2002             : 
    2003     2985654 :         if (pgstat_info->trans == NULL ||
    2004     1463800 :             pgstat_info->trans->nest_level != nest_level)
    2005       58142 :             add_tabstat_xact_level(pgstat_info, nest_level);
    2006             : 
    2007     1521854 :         pgstat_info->trans->tuples_deleted++;
    2008             :     }
    2009     1549694 : }
    2010             : 
    2011             : /*
    2012             :  * pgstat_truncate_save_counters
    2013             :  *
    2014             :  * Whenever a table is truncated, we save its i/u/d counters so that they can
    2015             :  * be cleared, and if the (sub)xact that executed the truncate later aborts,
    2016             :  * the counters can be restored to the saved (pre-truncate) values.  Note we do
    2017             :  * this on the first truncate in any particular subxact level only.
    2018             :  */
    2019             : static void
    2020        1488 : pgstat_truncate_save_counters(PgStat_TableXactStatus *trans)
    2021             : {
    2022        1488 :     if (!trans->truncated)
    2023             :     {
    2024        1404 :         trans->inserted_pre_trunc = trans->tuples_inserted;
    2025        1404 :         trans->updated_pre_trunc = trans->tuples_updated;
    2026        1404 :         trans->deleted_pre_trunc = trans->tuples_deleted;
    2027        1404 :         trans->truncated = true;
    2028             :     }
    2029        1488 : }
    2030             : 
    2031             : /*
    2032             :  * pgstat_truncate_restore_counters - restore counters when a truncate aborts
    2033             :  */
    2034             : static void
    2035        9280 : pgstat_truncate_restore_counters(PgStat_TableXactStatus *trans)
    2036             : {
    2037        9280 :     if (trans->truncated)
    2038             :     {
    2039          72 :         trans->tuples_inserted = trans->inserted_pre_trunc;
    2040          72 :         trans->tuples_updated = trans->updated_pre_trunc;
    2041          72 :         trans->tuples_deleted = trans->deleted_pre_trunc;
    2042             :     }
    2043        9280 : }
    2044             : 
    2045             : /*
    2046             :  * pgstat_count_truncate - update tuple counters due to truncate
    2047             :  */
    2048             : void
    2049        1472 : pgstat_count_truncate(Relation rel)
    2050             : {
    2051        1472 :     PgStat_TableStatus *pgstat_info = rel->pgstat_info;
    2052             : 
    2053        1472 :     if (pgstat_info != NULL)
    2054             :     {
    2055             :         /* We have to log the effect at the proper transactional level */
    2056        1472 :         int         nest_level = GetCurrentTransactionNestLevel();
    2057             : 
    2058        1580 :         if (pgstat_info->trans == NULL ||
    2059         108 :             pgstat_info->trans->nest_level != nest_level)
    2060        1380 :             add_tabstat_xact_level(pgstat_info, nest_level);
    2061             : 
    2062        1472 :         pgstat_truncate_save_counters(pgstat_info->trans);
    2063        1472 :         pgstat_info->trans->tuples_inserted = 0;
    2064        1472 :         pgstat_info->trans->tuples_updated = 0;
    2065        1472 :         pgstat_info->trans->tuples_deleted = 0;
    2066             :     }
    2067        1472 : }
    2068             : 
    2069             : /*
    2070             :  * pgstat_update_heap_dead_tuples - update dead-tuples count
    2071             :  *
    2072             :  * The semantics of this are that we are reporting the nontransactional
    2073             :  * recovery of "delta" dead tuples; so t_delta_dead_tuples decreases
    2074             :  * rather than increasing, and the change goes straight into the per-table
    2075             :  * counter, not into transactional state.
    2076             :  */
    2077             : void
    2078       31726 : pgstat_update_heap_dead_tuples(Relation rel, int delta)
    2079             : {
    2080       31726 :     PgStat_TableStatus *pgstat_info = rel->pgstat_info;
    2081             : 
    2082       31726 :     if (pgstat_info != NULL)
    2083       12206 :         pgstat_info->t_counts.t_delta_dead_tuples -= delta;
    2084       31726 : }
    2085             : 
    2086             : 
    2087             : /* ----------
    2088             :  * AtEOXact_PgStat
    2089             :  *
    2090             :  *  Called from access/transam/xact.c at top-level transaction commit/abort.
    2091             :  * ----------
    2092             :  */
    2093             : void
    2094      460474 : AtEOXact_PgStat(bool isCommit, bool parallel)
    2095             : {
    2096             :     PgStat_SubXactStatus *xact_state;
    2097             : 
    2098             :     /* Don't count parallel worker transaction stats */
    2099      460474 :     if (!parallel)
    2100             :     {
    2101             :         /*
    2102             :          * Count transaction commit or abort.  (We use counters, not just
    2103             :          * bools, in case the reporting message isn't sent right away.)
    2104             :          */
    2105      458844 :         if (isCommit)
    2106      439834 :             pgStatXactCommit++;
    2107             :         else
    2108       19010 :             pgStatXactRollback++;
    2109             :     }
    2110             : 
    2111             :     /*
    2112             :      * Transfer transactional insert/update counts into the base tabstat
    2113             :      * entries.  We don't bother to free any of the transactional state, since
    2114             :      * it's all in TopTransactionContext and will go away anyway.
    2115             :      */
    2116      460474 :     xact_state = pgStatXactStack;
    2117      460474 :     if (xact_state != NULL)
    2118             :     {
    2119             :         PgStat_TableXactStatus *trans;
    2120             : 
    2121             :         Assert(xact_state->nest_level == 1);
    2122             :         Assert(xact_state->prev == NULL);
    2123      334976 :         for (trans = xact_state->first; trans != NULL; trans = trans->next)
    2124             :         {
    2125             :             PgStat_TableStatus *tabstat;
    2126             : 
    2127             :             Assert(trans->nest_level == 1);
    2128             :             Assert(trans->upper == NULL);
    2129      249302 :             tabstat = trans->parent;
    2130             :             Assert(tabstat->trans == trans);
    2131             :             /* restore pre-truncate stats (if any) in case of aborted xact */
    2132      249302 :             if (!isCommit)
    2133        8790 :                 pgstat_truncate_restore_counters(trans);
    2134             :             /* count attempted actions regardless of commit/abort */
    2135      249302 :             tabstat->t_counts.t_tuples_inserted += trans->tuples_inserted;
    2136      249302 :             tabstat->t_counts.t_tuples_updated += trans->tuples_updated;
    2137      249302 :             tabstat->t_counts.t_tuples_deleted += trans->tuples_deleted;
    2138      249302 :             if (isCommit)
    2139             :             {
    2140      240512 :                 tabstat->t_counts.t_truncated = trans->truncated;
    2141      240512 :                 if (trans->truncated)
    2142             :                 {
    2143             :                     /* forget live/dead stats seen by backend thus far */
    2144        1316 :                     tabstat->t_counts.t_delta_live_tuples = 0;
    2145        1316 :                     tabstat->t_counts.t_delta_dead_tuples = 0;
    2146             :                 }
    2147             :                 /* insert adds a live tuple, delete removes one */
    2148      481024 :                 tabstat->t_counts.t_delta_live_tuples +=
    2149      240512 :                     trans->tuples_inserted - trans->tuples_deleted;
    2150             :                 /* update and delete each create a dead tuple */
    2151      481024 :                 tabstat->t_counts.t_delta_dead_tuples +=
    2152      240512 :                     trans->tuples_updated + trans->tuples_deleted;
    2153             :                 /* insert, update, delete each count as one change event */
    2154      481024 :                 tabstat->t_counts.t_changed_tuples +=
    2155      481024 :                     trans->tuples_inserted + trans->tuples_updated +
    2156      240512 :                     trans->tuples_deleted;
    2157             :             }
    2158             :             else
    2159             :             {
    2160             :                 /* inserted tuples are dead, deleted tuples are unaffected */
    2161       17580 :                 tabstat->t_counts.t_delta_dead_tuples +=
    2162        8790 :                     trans->tuples_inserted + trans->tuples_updated;
    2163             :                 /* an aborted xact generates no changed_tuple events */
    2164             :             }
    2165      249302 :             tabstat->trans = NULL;
    2166             :         }
    2167             :     }
    2168      460474 :     pgStatXactStack = NULL;
    2169             : 
    2170             :     /* Make sure any stats snapshot is thrown away */
    2171      460474 :     pgstat_clear_snapshot();
    2172      460474 : }
    2173             : 
    2174             : /* ----------
    2175             :  * AtEOSubXact_PgStat
    2176             :  *
    2177             :  *  Called from access/transam/xact.c at subtransaction commit/abort.
    2178             :  * ----------
    2179             :  */
    2180             : void
    2181        7352 : AtEOSubXact_PgStat(bool isCommit, int nestDepth)
    2182             : {
    2183             :     PgStat_SubXactStatus *xact_state;
    2184             : 
    2185             :     /*
    2186             :      * Transfer transactional insert/update counts into the next higher
    2187             :      * subtransaction state.
    2188             :      */
    2189        7352 :     xact_state = pgStatXactStack;
    2190       11662 :     if (xact_state != NULL &&
    2191        4310 :         xact_state->nest_level >= nestDepth)
    2192             :     {
    2193             :         PgStat_TableXactStatus *trans;
    2194             :         PgStat_TableXactStatus *next_trans;
    2195             : 
    2196             :         /* delink xact_state from stack immediately to simplify reuse case */
    2197        3886 :         pgStatXactStack = xact_state->prev;
    2198             : 
    2199        8090 :         for (trans = xact_state->first; trans != NULL; trans = next_trans)
    2200             :         {
    2201             :             PgStat_TableStatus *tabstat;
    2202             : 
    2203        4204 :             next_trans = trans->next;
    2204             :             Assert(trans->nest_level == nestDepth);
    2205        4204 :             tabstat = trans->parent;
    2206             :             Assert(tabstat->trans == trans);
    2207        4204 :             if (isCommit)
    2208             :             {
    2209        3714 :                 if (trans->upper && trans->upper->nest_level == nestDepth - 1)
    2210             :                 {
    2211        3076 :                     if (trans->truncated)
    2212             :                     {
    2213             :                         /* propagate the truncate status one level up */
    2214          16 :                         pgstat_truncate_save_counters(trans->upper);
    2215             :                         /* replace upper xact stats with ours */
    2216          16 :                         trans->upper->tuples_inserted = trans->tuples_inserted;
    2217          16 :                         trans->upper->tuples_updated = trans->tuples_updated;
    2218          16 :                         trans->upper->tuples_deleted = trans->tuples_deleted;
    2219             :                     }
    2220             :                     else
    2221             :                     {
    2222        3060 :                         trans->upper->tuples_inserted += trans->tuples_inserted;
    2223        3060 :                         trans->upper->tuples_updated += trans->tuples_updated;
    2224        3060 :                         trans->upper->tuples_deleted += trans->tuples_deleted;
    2225             :                     }
    2226        3076 :                     tabstat->trans = trans->upper;
    2227        3076 :                     pfree(trans);
    2228             :                 }
    2229             :                 else
    2230             :                 {
    2231             :                     /*
    2232             :                      * When there isn't an immediate parent state, we can just
    2233             :                      * reuse the record instead of going through a
    2234             :                      * palloc/pfree pushup (this works since it's all in
    2235             :                      * TopTransactionContext anyway).  We have to re-link it
    2236             :                      * into the parent level, though, and that might mean
    2237             :                      * pushing a new entry into the pgStatXactStack.
    2238             :                      */
    2239             :                     PgStat_SubXactStatus *upper_xact_state;
    2240             : 
    2241         638 :                     upper_xact_state = get_tabstat_stack_level(nestDepth - 1);
    2242         638 :                     trans->next = upper_xact_state->first;
    2243         638 :                     upper_xact_state->first = trans;
    2244         638 :                     trans->nest_level = nestDepth - 1;
    2245             :                 }
    2246             :             }
    2247             :             else
    2248             :             {
    2249             :                 /*
    2250             :                  * On abort, update top-level tabstat counts, then forget the
    2251             :                  * subtransaction
    2252             :                  */
    2253             : 
    2254             :                 /* first restore values obliterated by truncate */
    2255         490 :                 pgstat_truncate_restore_counters(trans);
    2256             :                 /* count attempted actions regardless of commit/abort */
    2257         490 :                 tabstat->t_counts.t_tuples_inserted += trans->tuples_inserted;
    2258         490 :                 tabstat->t_counts.t_tuples_updated += trans->tuples_updated;
    2259         490 :                 tabstat->t_counts.t_tuples_deleted += trans->tuples_deleted;
    2260             :                 /* inserted tuples are dead, deleted tuples are unaffected */
    2261         980 :                 tabstat->t_counts.t_delta_dead_tuples +=
    2262         490 :                     trans->tuples_inserted + trans->tuples_updated;
    2263         490 :                 tabstat->trans = trans->upper;
    2264         490 :                 pfree(trans);
    2265             :             }
    2266             :         }
    2267        3886 :         pfree(xact_state);
    2268             :     }
    2269        7352 : }
    2270             : 
    2271             : 
    2272             : /*
    2273             :  * AtPrepare_PgStat
    2274             :  *      Save the transactional stats state at 2PC transaction prepare.
    2275             :  *
    2276             :  * In this phase we just generate 2PC records for all the pending
    2277             :  * transaction-dependent stats work.
    2278             :  */
    2279             : void
    2280          58 : AtPrepare_PgStat(void)
    2281             : {
    2282             :     PgStat_SubXactStatus *xact_state;
    2283             : 
    2284          58 :     xact_state = pgStatXactStack;
    2285          58 :     if (xact_state != NULL)
    2286             :     {
    2287             :         PgStat_TableXactStatus *trans;
    2288             : 
    2289             :         Assert(xact_state->nest_level == 1);
    2290             :         Assert(xact_state->prev == NULL);
    2291         168 :         for (trans = xact_state->first; trans != NULL; trans = trans->next)
    2292             :         {
    2293             :             PgStat_TableStatus *tabstat;
    2294             :             TwoPhasePgStatRecord record;
    2295             : 
    2296             :             Assert(trans->nest_level == 1);
    2297             :             Assert(trans->upper == NULL);
    2298         112 :             tabstat = trans->parent;
    2299             :             Assert(tabstat->trans == trans);
    2300             : 
    2301         112 :             record.tuples_inserted = trans->tuples_inserted;
    2302         112 :             record.tuples_updated = trans->tuples_updated;
    2303         112 :             record.tuples_deleted = trans->tuples_deleted;
    2304         112 :             record.inserted_pre_trunc = trans->inserted_pre_trunc;
    2305         112 :             record.updated_pre_trunc = trans->updated_pre_trunc;
    2306         112 :             record.deleted_pre_trunc = trans->deleted_pre_trunc;
    2307         112 :             record.t_id = tabstat->t_id;
    2308         112 :             record.t_shared = tabstat->t_shared;
    2309         112 :             record.t_truncated = trans->truncated;
    2310             : 
    2311         112 :             RegisterTwoPhaseRecord(TWOPHASE_RM_PGSTAT_ID, 0,
    2312             :                                    &record, sizeof(TwoPhasePgStatRecord));
    2313             :         }
    2314             :     }
    2315          58 : }
    2316             : 
    2317             : /*
    2318             :  * PostPrepare_PgStat
    2319             :  *      Clean up after successful PREPARE.
    2320             :  *
    2321             :  * All we need do here is unlink the transaction stats state from the
    2322             :  * nontransactional state.  The nontransactional action counts will be
    2323             :  * reported to the stats collector immediately, while the effects on live
    2324             :  * and dead tuple counts are preserved in the 2PC state file.
    2325             :  *
    2326             :  * Note: AtEOXact_PgStat is not called during PREPARE.
    2327             :  */
    2328             : void
    2329          58 : PostPrepare_PgStat(void)
    2330             : {
    2331             :     PgStat_SubXactStatus *xact_state;
    2332             : 
    2333             :     /*
    2334             :      * We don't bother to free any of the transactional state, since it's all
    2335             :      * in TopTransactionContext and will go away anyway.
    2336             :      */
    2337          58 :     xact_state = pgStatXactStack;
    2338          58 :     if (xact_state != NULL)
    2339             :     {
    2340             :         PgStat_TableXactStatus *trans;
    2341             : 
    2342         168 :         for (trans = xact_state->first; trans != NULL; trans = trans->next)
    2343             :         {
    2344             :             PgStat_TableStatus *tabstat;
    2345             : 
    2346         112 :             tabstat = trans->parent;
    2347         112 :             tabstat->trans = NULL;
    2348             :         }
    2349             :     }
    2350          58 :     pgStatXactStack = NULL;
    2351             : 
    2352             :     /* Make sure any stats snapshot is thrown away */
    2353          58 :     pgstat_clear_snapshot();
    2354          58 : }
    2355             : 
    2356             : /*
    2357             :  * 2PC processing routine for COMMIT PREPARED case.
    2358             :  *
    2359             :  * Load the saved counts into our local pgstats state.
    2360             :  */
    2361             : void
    2362         102 : pgstat_twophase_postcommit(TransactionId xid, uint16 info,
    2363             :                            void *recdata, uint32 len)
    2364             : {
    2365         102 :     TwoPhasePgStatRecord *rec = (TwoPhasePgStatRecord *) recdata;
    2366             :     PgStat_TableStatus *pgstat_info;
    2367             : 
    2368             :     /* Find or create a tabstat entry for the rel */
    2369         102 :     pgstat_info = get_tabstat_entry(rec->t_id, rec->t_shared);
    2370             : 
    2371             :     /* Same math as in AtEOXact_PgStat, commit case */
    2372         102 :     pgstat_info->t_counts.t_tuples_inserted += rec->tuples_inserted;
    2373         102 :     pgstat_info->t_counts.t_tuples_updated += rec->tuples_updated;
    2374         102 :     pgstat_info->t_counts.t_tuples_deleted += rec->tuples_deleted;
    2375         102 :     pgstat_info->t_counts.t_truncated = rec->t_truncated;
    2376         102 :     if (rec->t_truncated)
    2377             :     {
    2378             :         /* forget live/dead stats seen by backend thus far */
    2379           0 :         pgstat_info->t_counts.t_delta_live_tuples = 0;
    2380           0 :         pgstat_info->t_counts.t_delta_dead_tuples = 0;
    2381             :     }
    2382         204 :     pgstat_info->t_counts.t_delta_live_tuples +=
    2383         102 :         rec->tuples_inserted - rec->tuples_deleted;
    2384         204 :     pgstat_info->t_counts.t_delta_dead_tuples +=
    2385         102 :         rec->tuples_updated + rec->tuples_deleted;
    2386         204 :     pgstat_info->t_counts.t_changed_tuples +=
    2387         204 :         rec->tuples_inserted + rec->tuples_updated +
    2388         102 :         rec->tuples_deleted;
    2389         102 : }
    2390             : 
    2391             : /*
    2392             :  * 2PC processing routine for ROLLBACK PREPARED case.
    2393             :  *
    2394             :  * Load the saved counts into our local pgstats state, but treat them
    2395             :  * as aborted.
    2396             :  */
    2397             : void
    2398          38 : pgstat_twophase_postabort(TransactionId xid, uint16 info,
    2399             :                           void *recdata, uint32 len)
    2400             : {
    2401          38 :     TwoPhasePgStatRecord *rec = (TwoPhasePgStatRecord *) recdata;
    2402             :     PgStat_TableStatus *pgstat_info;
    2403             : 
    2404             :     /* Find or create a tabstat entry for the rel */
    2405          38 :     pgstat_info = get_tabstat_entry(rec->t_id, rec->t_shared);
    2406             : 
    2407             :     /* Same math as in AtEOXact_PgStat, abort case */
    2408          38 :     if (rec->t_truncated)
    2409             :     {
    2410           0 :         rec->tuples_inserted = rec->inserted_pre_trunc;
    2411           0 :         rec->tuples_updated = rec->updated_pre_trunc;
    2412           0 :         rec->tuples_deleted = rec->deleted_pre_trunc;
    2413             :     }
    2414          38 :     pgstat_info->t_counts.t_tuples_inserted += rec->tuples_inserted;
    2415          38 :     pgstat_info->t_counts.t_tuples_updated += rec->tuples_updated;
    2416          38 :     pgstat_info->t_counts.t_tuples_deleted += rec->tuples_deleted;
    2417          76 :     pgstat_info->t_counts.t_delta_dead_tuples +=
    2418          38 :         rec->tuples_inserted + rec->tuples_updated;
    2419          38 : }
    2420             : 
    2421             : 
    2422             : /* ----------
    2423             :  * pgstat_fetch_stat_dbentry() -
    2424             :  *
    2425             :  *  Support function for the SQL-callable pgstat* functions. Returns
    2426             :  *  the collected statistics for one database or NULL. NULL doesn't mean
    2427             :  *  that the database doesn't exist, it is just not yet known by the
    2428             :  *  collector, so the caller is better off to report ZERO instead.
    2429             :  * ----------
    2430             :  */
    2431             : PgStat_StatDBEntry *
    2432        3278 : pgstat_fetch_stat_dbentry(Oid dbid)
    2433             : {
    2434             :     /*
    2435             :      * If not done for this transaction, read the statistics collector stats
    2436             :      * file into some hash tables.
    2437             :      */
    2438        3278 :     backend_read_statsfile();
    2439             : 
    2440             :     /*
    2441             :      * Lookup the requested database; return NULL if not found
    2442             :      */
    2443        3278 :     return (PgStat_StatDBEntry *) hash_search(pgStatDBHash,
    2444             :                                               (void *) &dbid,
    2445             :                                               HASH_FIND, NULL);
    2446             : }
    2447             : 
    2448             : 
    2449             : /* ----------
    2450             :  * pgstat_fetch_stat_tabentry() -
    2451             :  *
    2452             :  *  Support function for the SQL-callable pgstat* functions. Returns
    2453             :  *  the collected statistics for one table or NULL. NULL doesn't mean
    2454             :  *  that the table doesn't exist, it is just not yet known by the
    2455             :  *  collector, so the caller is better off to report ZERO instead.
    2456             :  * ----------
    2457             :  */
    2458             : PgStat_StatTabEntry *
    2459         682 : pgstat_fetch_stat_tabentry(Oid relid)
    2460             : {
    2461             :     Oid         dbid;
    2462             :     PgStat_StatDBEntry *dbentry;
    2463             :     PgStat_StatTabEntry *tabentry;
    2464             : 
    2465             :     /*
    2466             :      * If not done for this transaction, read the statistics collector stats
    2467             :      * file into some hash tables.
    2468             :      */
    2469         682 :     backend_read_statsfile();
    2470             : 
    2471             :     /*
    2472             :      * Lookup our database, then look in its table hash table.
    2473             :      */
    2474         682 :     dbid = MyDatabaseId;
    2475         682 :     dbentry = (PgStat_StatDBEntry *) hash_search(pgStatDBHash,
    2476             :                                                  (void *) &dbid,
    2477             :                                                  HASH_FIND, NULL);
    2478         682 :     if (dbentry != NULL && dbentry->tables != NULL)
    2479             :     {
    2480         682 :         tabentry = (PgStat_StatTabEntry *) hash_search(dbentry->tables,
    2481             :                                                        (void *) &relid,
    2482             :                                                        HASH_FIND, NULL);
    2483         682 :         if (tabentry)
    2484         546 :             return tabentry;
    2485             :     }
    2486             : 
    2487             :     /*
    2488             :      * If we didn't find it, maybe it's a shared table.
    2489             :      */
    2490         136 :     dbid = InvalidOid;
    2491         136 :     dbentry = (PgStat_StatDBEntry *) hash_search(pgStatDBHash,
    2492             :                                                  (void *) &dbid,
    2493             :                                                  HASH_FIND, NULL);
    2494         136 :     if (dbentry != NULL && dbentry->tables != NULL)
    2495             :     {
    2496         136 :         tabentry = (PgStat_StatTabEntry *) hash_search(dbentry->tables,
    2497             :                                                        (void *) &relid,
    2498             :                                                        HASH_FIND, NULL);
    2499         136 :         if (tabentry)
    2500           0 :             return tabentry;
    2501             :     }
    2502             : 
    2503         136 :     return NULL;
    2504             : }
    2505             : 
    2506             : 
    2507             : /* ----------
    2508             :  * pgstat_fetch_stat_funcentry() -
    2509             :  *
    2510             :  *  Support function for the SQL-callable pgstat* functions. Returns
    2511             :  *  the collected statistics for one function or NULL.
    2512             :  * ----------
    2513             :  */
    2514             : PgStat_StatFuncEntry *
    2515           0 : pgstat_fetch_stat_funcentry(Oid func_id)
    2516             : {
    2517             :     PgStat_StatDBEntry *dbentry;
    2518           0 :     PgStat_StatFuncEntry *funcentry = NULL;
    2519             : 
    2520             :     /* load the stats file if needed */
    2521           0 :     backend_read_statsfile();
    2522             : 
    2523             :     /* Lookup our database, then find the requested function.  */
    2524           0 :     dbentry = pgstat_fetch_stat_dbentry(MyDatabaseId);
    2525           0 :     if (dbentry != NULL && dbentry->functions != NULL)
    2526             :     {
    2527           0 :         funcentry = (PgStat_StatFuncEntry *) hash_search(dbentry->functions,
    2528             :                                                          (void *) &func_id,
    2529             :                                                          HASH_FIND, NULL);
    2530             :     }
    2531             : 
    2532           0 :     return funcentry;
    2533             : }
    2534             : 
    2535             : 
    2536             : /* ----------
    2537             :  * pgstat_fetch_stat_beentry() -
    2538             :  *
    2539             :  *  Support function for the SQL-callable pgstat* functions. Returns
    2540             :  *  our local copy of the current-activity entry for one backend.
    2541             :  *
    2542             :  *  NB: caller is responsible for a check if the user is permitted to see
    2543             :  *  this info (especially the querystring).
    2544             :  * ----------
    2545             :  */
    2546             : PgBackendStatus *
    2547           0 : pgstat_fetch_stat_beentry(int beid)
    2548             : {
    2549           0 :     pgstat_read_current_status();
    2550             : 
    2551           0 :     if (beid < 1 || beid > localNumBackends)
    2552           0 :         return NULL;
    2553             : 
    2554           0 :     return &localBackendStatusTable[beid - 1].backendStatus;
    2555             : }
    2556             : 
    2557             : 
    2558             : /* ----------
    2559             :  * pgstat_fetch_stat_local_beentry() -
    2560             :  *
    2561             :  *  Like pgstat_fetch_stat_beentry() but with locally computed additions (like
    2562             :  *  xid and xmin values of the backend)
    2563             :  *
    2564             :  *  NB: caller is responsible for a check if the user is permitted to see
    2565             :  *  this info (especially the querystring).
    2566             :  * ----------
    2567             :  */
    2568             : LocalPgBackendStatus *
    2569        1522 : pgstat_fetch_stat_local_beentry(int beid)
    2570             : {
    2571        1522 :     pgstat_read_current_status();
    2572             : 
    2573        1522 :     if (beid < 1 || beid > localNumBackends)
    2574           0 :         return NULL;
    2575             : 
    2576        1522 :     return &localBackendStatusTable[beid - 1];
    2577             : }
    2578             : 
    2579             : 
    2580             : /* ----------
    2581             :  * pgstat_fetch_stat_numbackends() -
    2582             :  *
    2583             :  *  Support function for the SQL-callable pgstat* functions. Returns
    2584             :  *  the maximum current backend id.
    2585             :  * ----------
    2586             :  */
    2587             : int
    2588         208 : pgstat_fetch_stat_numbackends(void)
    2589             : {
    2590         208 :     pgstat_read_current_status();
    2591             : 
    2592         208 :     return localNumBackends;
    2593             : }
    2594             : 
    2595             : /*
    2596             :  * ---------
    2597             :  * pgstat_fetch_stat_archiver() -
    2598             :  *
    2599             :  *  Support function for the SQL-callable pgstat* functions. Returns
    2600             :  *  a pointer to the archiver statistics struct.
    2601             :  * ---------
    2602             :  */
    2603             : PgStat_ArchiverStats *
    2604           0 : pgstat_fetch_stat_archiver(void)
    2605             : {
    2606           0 :     backend_read_statsfile();
    2607             : 
    2608           0 :     return &archiverStats;
    2609             : }
    2610             : 
    2611             : 
    2612             : /*
    2613             :  * ---------
    2614             :  * pgstat_fetch_global() -
    2615             :  *
    2616             :  *  Support function for the SQL-callable pgstat* functions. Returns
    2617             :  *  a pointer to the global statistics struct.
    2618             :  * ---------
    2619             :  */
    2620             : PgStat_GlobalStats *
    2621          28 : pgstat_fetch_global(void)
    2622             : {
    2623          28 :     backend_read_statsfile();
    2624             : 
    2625          28 :     return &globalStats;
    2626             : }
    2627             : 
    2628             : 
    2629             : /* ------------------------------------------------------------
    2630             :  * Functions for management of the shared-memory PgBackendStatus array
    2631             :  * ------------------------------------------------------------
    2632             :  */
    2633             : 
    2634             : static PgBackendStatus *BackendStatusArray = NULL;
    2635             : static PgBackendStatus *MyBEEntry = NULL;
    2636             : static char *BackendAppnameBuffer = NULL;
    2637             : static char *BackendClientHostnameBuffer = NULL;
    2638             : static char *BackendActivityBuffer = NULL;
    2639             : static Size BackendActivityBufferSize = 0;
    2640             : #ifdef USE_SSL
    2641             : static PgBackendSSLStatus *BackendSslStatusBuffer = NULL;
    2642             : #endif
    2643             : #ifdef ENABLE_GSS
    2644             : static PgBackendGSSStatus *BackendGssStatusBuffer = NULL;
    2645             : #endif
    2646             : 
    2647             : 
    2648             : /*
    2649             :  * Report shared-memory space needed by CreateSharedBackendStatus.
    2650             :  */
    2651             : Size
    2652        1862 : BackendStatusShmemSize(void)
    2653             : {
    2654             :     Size        size;
    2655             : 
    2656             :     /* BackendStatusArray: */
    2657        1862 :     size = mul_size(sizeof(PgBackendStatus), NumBackendStatSlots);
    2658             :     /* BackendAppnameBuffer: */
    2659        1862 :     size = add_size(size,
    2660        1862 :                     mul_size(NAMEDATALEN, NumBackendStatSlots));
    2661             :     /* BackendClientHostnameBuffer: */
    2662        1862 :     size = add_size(size,
    2663        1862 :                     mul_size(NAMEDATALEN, NumBackendStatSlots));
    2664             :     /* BackendActivityBuffer: */
    2665        1862 :     size = add_size(size,
    2666        1862 :                     mul_size(pgstat_track_activity_query_size, NumBackendStatSlots));
    2667             : #ifdef USE_SSL
    2668             :     /* BackendSslStatusBuffer: */
    2669        1862 :     size = add_size(size,
    2670        1862 :                     mul_size(sizeof(PgBackendSSLStatus), NumBackendStatSlots));
    2671             : #endif
    2672        1862 :     return size;
    2673             : }
    2674             : 
    2675             : /*
    2676             :  * Initialize the shared status array and several string buffers
    2677             :  * during postmaster startup.
    2678             :  */
    2679             : void
    2680        1858 : CreateSharedBackendStatus(void)
    2681             : {
    2682             :     Size        size;
    2683             :     bool        found;
    2684             :     int         i;
    2685             :     char       *buffer;
    2686             : 
    2687             :     /* Create or attach to the shared array */
    2688        1858 :     size = mul_size(sizeof(PgBackendStatus), NumBackendStatSlots);
    2689        1858 :     BackendStatusArray = (PgBackendStatus *)
    2690        1858 :         ShmemInitStruct("Backend Status Array", size, &found);
    2691             : 
    2692        1858 :     if (!found)
    2693             :     {
    2694             :         /*
    2695             :          * We're the first - initialize.
    2696             :          */
    2697        1858 :         MemSet(BackendStatusArray, 0, size);
    2698             :     }
    2699             : 
    2700             :     /* Create or attach to the shared appname buffer */
    2701        1858 :     size = mul_size(NAMEDATALEN, NumBackendStatSlots);
    2702        1858 :     BackendAppnameBuffer = (char *)
    2703        1858 :         ShmemInitStruct("Backend Application Name Buffer", size, &found);
    2704             : 
    2705        1858 :     if (!found)
    2706             :     {
    2707        1858 :         MemSet(BackendAppnameBuffer, 0, size);
    2708             : 
    2709             :         /* Initialize st_appname pointers. */
    2710        1858 :         buffer = BackendAppnameBuffer;
    2711      211436 :         for (i = 0; i < NumBackendStatSlots; i++)
    2712             :         {
    2713      209578 :             BackendStatusArray[i].st_appname = buffer;
    2714      209578 :             buffer += NAMEDATALEN;
    2715             :         }
    2716             :     }
    2717             : 
    2718             :     /* Create or attach to the shared client hostname buffer */
    2719        1858 :     size = mul_size(NAMEDATALEN, NumBackendStatSlots);
    2720        1858 :     BackendClientHostnameBuffer = (char *)
    2721        1858 :         ShmemInitStruct("Backend Client Host Name Buffer", size, &found);
    2722             : 
    2723        1858 :     if (!found)
    2724             :     {
    2725        1858 :         MemSet(BackendClientHostnameBuffer, 0, size);
    2726             : 
    2727             :         /* Initialize st_clienthostname pointers. */
    2728        1858 :         buffer = BackendClientHostnameBuffer;
    2729      211436 :         for (i = 0; i < NumBackendStatSlots; i++)
    2730             :         {
    2731      209578 :             BackendStatusArray[i].st_clienthostname = buffer;
    2732      209578 :             buffer += NAMEDATALEN;
    2733             :         }
    2734             :     }
    2735             : 
    2736             :     /* Create or attach to the shared activity buffer */
    2737        1858 :     BackendActivityBufferSize = mul_size(pgstat_track_activity_query_size,
    2738        1858 :                                          NumBackendStatSlots);
    2739        1858 :     BackendActivityBuffer = (char *)
    2740        1858 :         ShmemInitStruct("Backend Activity Buffer",
    2741             :                         BackendActivityBufferSize,
    2742             :                         &found);
    2743             : 
    2744        1858 :     if (!found)
    2745             :     {
    2746        1858 :         MemSet(BackendActivityBuffer, 0, BackendActivityBufferSize);
    2747             : 
    2748             :         /* Initialize st_activity pointers. */
    2749        1858 :         buffer = BackendActivityBuffer;
    2750      211436 :         for (i = 0; i < NumBackendStatSlots; i++)
    2751             :         {
    2752      209578 :             BackendStatusArray[i].st_activity_raw = buffer;
    2753      209578 :             buffer += pgstat_track_activity_query_size;
    2754             :         }
    2755             :     }
    2756             : 
    2757             : #ifdef USE_SSL
    2758             :     /* Create or attach to the shared SSL status buffer */
    2759        1858 :     size = mul_size(sizeof(PgBackendSSLStatus), NumBackendStatSlots);
    2760        1858 :     BackendSslStatusBuffer = (PgBackendSSLStatus *)
    2761        1858 :         ShmemInitStruct("Backend SSL Status Buffer", size, &found);
    2762             : 
    2763        1858 :     if (!found)
    2764             :     {
    2765             :         PgBackendSSLStatus *ptr;
    2766             : 
    2767        1858 :         MemSet(BackendSslStatusBuffer, 0, size);
    2768             : 
    2769             :         /* Initialize st_sslstatus pointers. */
    2770        1858 :         ptr = BackendSslStatusBuffer;
    2771      211436 :         for (i = 0; i < NumBackendStatSlots; i++)
    2772             :         {
    2773      209578 :             BackendStatusArray[i].st_sslstatus = ptr;
    2774      209578 :             ptr++;
    2775             :         }
    2776             :     }
    2777             : #endif
    2778             : 
    2779             : #ifdef ENABLE_GSS
    2780             :     /* Create or attach to the shared GSSAPI status buffer */
    2781             :     size = mul_size(sizeof(PgBackendGSSStatus), NumBackendStatSlots);
    2782             :     BackendGssStatusBuffer = (PgBackendGSSStatus *)
    2783             :         ShmemInitStruct("Backend GSS Status Buffer", size, &found);
    2784             : 
    2785             :     if (!found)
    2786             :     {
    2787             :         PgBackendGSSStatus *ptr;
    2788             : 
    2789             :         MemSet(BackendGssStatusBuffer, 0, size);
    2790             : 
    2791             :         /* Initialize st_gssstatus pointers. */
    2792             :         ptr = BackendGssStatusBuffer;
    2793             :         for (i = 0; i < NumBackendStatSlots; i++)
    2794             :         {
    2795             :             BackendStatusArray[i].st_gssstatus = ptr;
    2796             :             ptr++;
    2797             :         }
    2798             :     }
    2799             : #endif
    2800        1858 : }
    2801             : 
    2802             : 
    2803             : /* ----------
    2804             :  * pgstat_initialize() -
    2805             :  *
    2806             :  *  Initialize pgstats state, and set up our on-proc-exit hook.
    2807             :  *  Called from InitPostgres and AuxiliaryProcessMain. For auxiliary process,
    2808             :  *  MyBackendId is invalid. Otherwise, MyBackendId must be set,
    2809             :  *  but we must not have started any transaction yet (since the
    2810             :  *  exit hook must run after the last transaction exit).
    2811             :  *  NOTE: MyDatabaseId isn't set yet; so the shutdown hook has to be careful.
    2812             :  * ----------
    2813             :  */
    2814             : void
    2815       11278 : pgstat_initialize(void)
    2816             : {
    2817             :     /* Initialize MyBEEntry */
    2818       11278 :     if (MyBackendId != InvalidBackendId)
    2819             :     {
    2820             :         Assert(MyBackendId >= 1 && MyBackendId <= MaxBackends);
    2821        9450 :         MyBEEntry = &BackendStatusArray[MyBackendId - 1];
    2822             :     }
    2823             :     else
    2824             :     {
    2825             :         /* Must be an auxiliary process */
    2826             :         Assert(MyAuxProcType != NotAnAuxProcess);
    2827             : 
    2828             :         /*
    2829             :          * Assign the MyBEEntry for an auxiliary process.  Since it doesn't
    2830             :          * have a BackendId, the slot is statically allocated based on the
    2831             :          * auxiliary process type (MyAuxProcType).  Backends use slots indexed
    2832             :          * in the range from 1 to MaxBackends (inclusive), so we use
    2833             :          * MaxBackends + AuxBackendType + 1 as the index of the slot for an
    2834             :          * auxiliary process.
    2835             :          */
    2836        1828 :         MyBEEntry = &BackendStatusArray[MaxBackends + MyAuxProcType];
    2837             :     }
    2838             : 
    2839             :     /* Set up a process-exit hook to clean up */
    2840       11278 :     on_shmem_exit(pgstat_beshutdown_hook, 0);
    2841       11278 : }
    2842             : 
    2843             : /* ----------
    2844             :  * pgstat_bestart() -
    2845             :  *
    2846             :  *  Initialize this backend's entry in the PgBackendStatus array.
    2847             :  *  Called from InitPostgres.
    2848             :  *
    2849             :  *  Apart from auxiliary processes, MyBackendId, MyDatabaseId,
    2850             :  *  session userid, and application_name must be set for a
    2851             :  *  backend (hence, this cannot be combined with pgstat_initialize).
    2852             :  *  Note also that we must be inside a transaction if this isn't an aux
    2853             :  *  process, as we may need to do encoding conversion on some strings.
    2854             :  * ----------
    2855             :  */
    2856             : void
    2857       11212 : pgstat_bestart(void)
    2858             : {
    2859       11212 :     volatile PgBackendStatus *vbeentry = MyBEEntry;
    2860             :     PgBackendStatus lbeentry;
    2861             : #ifdef USE_SSL
    2862             :     PgBackendSSLStatus lsslstatus;
    2863             : #endif
    2864             : #ifdef ENABLE_GSS
    2865             :     PgBackendGSSStatus lgssstatus;
    2866             : #endif
    2867             : 
    2868             :     /* pgstats state must be initialized from pgstat_initialize() */
    2869             :     Assert(vbeentry != NULL);
    2870             : 
    2871             :     /*
    2872             :      * To minimize the time spent modifying the PgBackendStatus entry, and
    2873             :      * avoid risk of errors inside the critical section, we first copy the
    2874             :      * shared-memory struct to a local variable, then modify the data in the
    2875             :      * local variable, then copy the local variable back to shared memory.
    2876             :      * Only the last step has to be inside the critical section.
    2877             :      *
    2878             :      * Most of the data we copy from shared memory is just going to be
    2879             :      * overwritten, but the struct's not so large that it's worth the
    2880             :      * maintenance hassle to copy only the needful fields.
    2881             :      */
    2882       11212 :     memcpy(&lbeentry,
    2883       11212 :            unvolatize(PgBackendStatus *, vbeentry),
    2884             :            sizeof(PgBackendStatus));
    2885             : 
    2886             :     /* These structs can just start from zeroes each time, though */
    2887             : #ifdef USE_SSL
    2888       11212 :     memset(&lsslstatus, 0, sizeof(lsslstatus));
    2889             : #endif
    2890             : #ifdef ENABLE_GSS
    2891             :     memset(&lgssstatus, 0, sizeof(lgssstatus));
    2892             : #endif
    2893             : 
    2894             :     /*
    2895             :      * Now fill in all the fields of lbeentry, except for strings that are
    2896             :      * out-of-line data.  Those have to be handled separately, below.
    2897             :      */
    2898       11212 :     lbeentry.st_procpid = MyProcPid;
    2899             : 
    2900       11212 :     if (MyBackendId != InvalidBackendId)
    2901             :     {
    2902        9384 :         if (IsAutoVacuumLauncherProcess())
    2903             :         {
    2904             :             /* Autovacuum Launcher */
    2905         348 :             lbeentry.st_backendType = B_AUTOVAC_LAUNCHER;
    2906             :         }
    2907        9036 :         else if (IsAutoVacuumWorkerProcess())
    2908             :         {
    2909             :             /* Autovacuum Worker */
    2910          62 :             lbeentry.st_backendType = B_AUTOVAC_WORKER;
    2911             :         }
    2912        8974 :         else if (am_walsender)
    2913             :         {
    2914             :             /* Wal sender */
    2915         462 :             lbeentry.st_backendType = B_WAL_SENDER;
    2916             :         }
    2917        8512 :         else if (IsBackgroundWorker)
    2918             :         {
    2919             :             /* bgworker */
    2920        2116 :             lbeentry.st_backendType = B_BG_WORKER;
    2921             :         }
    2922             :         else
    2923             :         {
    2924             :             /* client-backend */
    2925        6396 :             lbeentry.st_backendType = B_BACKEND;
    2926             :         }
    2927             :     }
    2928             :     else
    2929             :     {
    2930             :         /* Must be an auxiliary process */
    2931             :         Assert(MyAuxProcType != NotAnAuxProcess);
    2932        1828 :         switch (MyAuxProcType)
    2933             :         {
    2934             :             case StartupProcess:
    2935         522 :                 lbeentry.st_backendType = B_STARTUP;
    2936         522 :                 break;
    2937             :             case BgWriterProcess:
    2938         382 :                 lbeentry.st_backendType = B_BG_WRITER;
    2939         382 :                 break;
    2940             :             case CheckpointerProcess:
    2941         382 :                 lbeentry.st_backendType = B_CHECKPOINTER;
    2942         382 :                 break;
    2943             :             case WalWriterProcess:
    2944         360 :                 lbeentry.st_backendType = B_WAL_WRITER;
    2945         360 :                 break;
    2946             :             case WalReceiverProcess:
    2947         182 :                 lbeentry.st_backendType = B_WAL_RECEIVER;
    2948         182 :                 break;
    2949             :             default:
    2950           0 :                 elog(FATAL, "unrecognized process type: %d",
    2951             :                      (int) MyAuxProcType);
    2952             :         }
    2953             :     }
    2954             : 
    2955       11212 :     lbeentry.st_proc_start_timestamp = MyStartTimestamp;
    2956       11212 :     lbeentry.st_activity_start_timestamp = 0;
    2957       11212 :     lbeentry.st_state_start_timestamp = 0;
    2958       11212 :     lbeentry.st_xact_start_timestamp = 0;
    2959       11212 :     lbeentry.st_databaseid = MyDatabaseId;
    2960             : 
    2961             :     /* We have userid for client-backends, wal-sender and bgworker processes */
    2962       11212 :     if (lbeentry.st_backendType == B_BACKEND
    2963        4816 :         || lbeentry.st_backendType == B_WAL_SENDER
    2964        4354 :         || lbeentry.st_backendType == B_BG_WORKER)
    2965        8974 :         lbeentry.st_userid = GetSessionUserId();
    2966             :     else
    2967        2238 :         lbeentry.st_userid = InvalidOid;
    2968             : 
    2969             :     /*
    2970             :      * We may not have a MyProcPort (eg, if this is the autovacuum process).
    2971             :      * If so, use all-zeroes client address, which is dealt with specially in
    2972             :      * pg_stat_get_backend_client_addr and pg_stat_get_backend_client_port.
    2973             :      */
    2974       11212 :     if (MyProcPort)
    2975        6538 :         memcpy(&lbeentry.st_clientaddr, &MyProcPort->raddr,
    2976             :                sizeof(lbeentry.st_clientaddr));
    2977             :     else
    2978        4674 :         MemSet(&lbeentry.st_clientaddr, 0, sizeof(lbeentry.st_clientaddr));
    2979             : 
    2980             : #ifdef USE_SSL
    2981       11212 :     if (MyProcPort && MyProcPort->ssl != NULL)
    2982             :     {
    2983          50 :         lbeentry.st_ssl = true;
    2984          50 :         lsslstatus.ssl_bits = be_tls_get_cipher_bits(MyProcPort);
    2985          50 :         lsslstatus.ssl_compression = be_tls_get_compression(MyProcPort);
    2986          50 :         strlcpy(lsslstatus.ssl_version, be_tls_get_version(MyProcPort), NAMEDATALEN);
    2987          50 :         strlcpy(lsslstatus.ssl_cipher, be_tls_get_cipher(MyProcPort), NAMEDATALEN);
    2988          50 :         be_tls_get_peer_subject_name(MyProcPort, lsslstatus.ssl_client_dn, NAMEDATALEN);
    2989          50 :         be_tls_get_peer_serial(MyProcPort, lsslstatus.ssl_client_serial, NAMEDATALEN);
    2990          50 :         be_tls_get_peer_issuer_name(MyProcPort, lsslstatus.ssl_issuer_dn, NAMEDATALEN);
    2991             :     }
    2992             :     else
    2993             :     {
    2994       11162 :         lbeentry.st_ssl = false;
    2995             :     }
    2996             : #else
    2997             :     lbeentry.st_ssl = false;
    2998             : #endif
    2999             : 
    3000             : #ifdef ENABLE_GSS
    3001             :     if (MyProcPort && MyProcPort->gss != NULL)
    3002             :     {
    3003             :         lbeentry.st_gss = true;
    3004             :         lgssstatus.gss_auth = be_gssapi_get_auth(MyProcPort);
    3005             :         lgssstatus.gss_enc = be_gssapi_get_enc(MyProcPort);
    3006             : 
    3007             :         if (lgssstatus.gss_auth)
    3008             :             strlcpy(lgssstatus.gss_princ, be_gssapi_get_princ(MyProcPort), NAMEDATALEN);
    3009             :     }
    3010             :     else
    3011             :     {
    3012             :         lbeentry.st_gss = false;
    3013             :     }
    3014             : #else
    3015       11212 :     lbeentry.st_gss = false;
    3016             : #endif
    3017             : 
    3018       11212 :     lbeentry.st_state = STATE_UNDEFINED;
    3019       11212 :     lbeentry.st_progress_command = PROGRESS_COMMAND_INVALID;
    3020       11212 :     lbeentry.st_progress_command_target = InvalidOid;
    3021             : 
    3022             :     /*
    3023             :      * we don't zero st_progress_param here to save cycles; nobody should
    3024             :      * examine it until st_progress_command has been set to something other
    3025             :      * than PROGRESS_COMMAND_INVALID
    3026             :      */
    3027             : 
    3028             :     /*
    3029             :      * We're ready to enter the critical section that fills the shared-memory
    3030             :      * status entry.  We follow the protocol of bumping st_changecount before
    3031             :      * and after; and make sure it's even afterwards.  We use a volatile
    3032             :      * pointer here to ensure the compiler doesn't try to get cute.
    3033             :      */
    3034       11212 :     PGSTAT_BEGIN_WRITE_ACTIVITY(vbeentry);
    3035             : 
    3036             :     /* make sure we'll memcpy the same st_changecount back */
    3037       11212 :     lbeentry.st_changecount = vbeentry->st_changecount;
    3038             : 
    3039       11212 :     memcpy(unvolatize(PgBackendStatus *, vbeentry),
    3040             :            &lbeentry,
    3041             :            sizeof(PgBackendStatus));
    3042             : 
    3043             :     /*
    3044             :      * We can write the out-of-line strings and structs using the pointers
    3045             :      * that are in lbeentry; this saves some de-volatilizing messiness.
    3046             :      */
    3047       11212 :     lbeentry.st_appname[0] = '\0';
    3048       11212 :     if (MyProcPort && MyProcPort->remote_hostname)
    3049          50 :         strlcpy(lbeentry.st_clienthostname, MyProcPort->remote_hostname,
    3050             :                 NAMEDATALEN);
    3051             :     else
    3052       11162 :         lbeentry.st_clienthostname[0] = '\0';
    3053       11212 :     lbeentry.st_activity_raw[0] = '\0';
    3054             :     /* Also make sure the last byte in each string area is always 0 */
    3055       11212 :     lbeentry.st_appname[NAMEDATALEN - 1] = '\0';
    3056       11212 :     lbeentry.st_clienthostname[NAMEDATALEN - 1] = '\0';
    3057       11212 :     lbeentry.st_activity_raw[pgstat_track_activity_query_size - 1] = '\0';
    3058             : 
    3059             : #ifdef USE_SSL
    3060       11212 :     memcpy(lbeentry.st_sslstatus, &lsslstatus, sizeof(PgBackendSSLStatus));
    3061             : #endif
    3062             : #ifdef ENABLE_GSS
    3063             :     memcpy(lbeentry.st_gssstatus, &lgssstatus, sizeof(PgBackendGSSStatus));
    3064             : #endif
    3065             : 
    3066       11212 :     PGSTAT_END_WRITE_ACTIVITY(vbeentry);
    3067             : 
    3068             :     /* Update app name to current GUC setting */
    3069       11212 :     if (application_name)
    3070       11212 :         pgstat_report_appname(application_name);
    3071       11212 : }
    3072             : 
    3073             : /*
    3074             :  * Shut down a single backend's statistics reporting at process exit.
    3075             :  *
    3076             :  * Flush any remaining statistics counts out to the collector.
    3077             :  * Without this, operations triggered during backend exit (such as
    3078             :  * temp table deletions) won't be counted.
    3079             :  *
    3080             :  * Lastly, clear out our entry in the PgBackendStatus array.
    3081             :  */
    3082             : static void
    3083       11278 : pgstat_beshutdown_hook(int code, Datum arg)
    3084             : {
    3085       11278 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3086             : 
    3087             :     /*
    3088             :      * If we got as far as discovering our own database ID, we can report what
    3089             :      * we did to the collector.  Otherwise, we'd be sending an invalid
    3090             :      * database ID, so forget it.  (This means that accesses to pg_database
    3091             :      * during failed backend starts might never get counted.)
    3092             :      */
    3093       11278 :     if (OidIsValid(MyDatabaseId))
    3094        8396 :         pgstat_report_stat(true);
    3095             : 
    3096             :     /*
    3097             :      * Clear my status entry, following the protocol of bumping st_changecount
    3098             :      * before and after.  We use a volatile pointer here to ensure the
    3099             :      * compiler doesn't try to get cute.
    3100             :      */
    3101       11278 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3102             : 
    3103       11278 :     beentry->st_procpid = 0; /* mark invalid */
    3104             : 
    3105       11278 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3106       11278 : }
    3107             : 
    3108             : 
    3109             : /* ----------
    3110             :  * pgstat_report_activity() -
    3111             :  *
    3112             :  *  Called from tcop/postgres.c to report what the backend is actually doing
    3113             :  *  (but note cmd_str can be NULL for certain cases).
    3114             :  *
    3115             :  * All updates of the status entry follow the protocol of bumping
    3116             :  * st_changecount before and after.  We use a volatile pointer here to
    3117             :  * ensure the compiler doesn't try to get cute.
    3118             :  * ----------
    3119             :  */
    3120             : void
    3121      945416 : pgstat_report_activity(BackendState state, const char *cmd_str)
    3122             : {
    3123      945416 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3124             :     TimestampTz start_timestamp;
    3125             :     TimestampTz current_timestamp;
    3126      945416 :     int         len = 0;
    3127             : 
    3128             :     TRACE_POSTGRESQL_STATEMENT_STATUS(cmd_str);
    3129             : 
    3130      945416 :     if (!beentry)
    3131           0 :         return;
    3132             : 
    3133      945416 :     if (!pgstat_track_activities)
    3134             :     {
    3135           0 :         if (beentry->st_state != STATE_DISABLED)
    3136             :         {
    3137           0 :             volatile PGPROC *proc = MyProc;
    3138             : 
    3139             :             /*
    3140             :              * track_activities is disabled, but we last reported a
    3141             :              * non-disabled state.  As our final update, change the state and
    3142             :              * clear fields we will not be updating anymore.
    3143             :              */
    3144           0 :             PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3145           0 :             beentry->st_state = STATE_DISABLED;
    3146           0 :             beentry->st_state_start_timestamp = 0;
    3147           0 :             beentry->st_activity_raw[0] = '\0';
    3148           0 :             beentry->st_activity_start_timestamp = 0;
    3149             :             /* st_xact_start_timestamp and wait_event_info are also disabled */
    3150           0 :             beentry->st_xact_start_timestamp = 0;
    3151           0 :             proc->wait_event_info = 0;
    3152           0 :             PGSTAT_END_WRITE_ACTIVITY(beentry);
    3153             :         }
    3154           0 :         return;
    3155             :     }
    3156             : 
    3157             :     /*
    3158             :      * To minimize the time spent modifying the entry, and avoid risk of
    3159             :      * errors inside the critical section, fetch all the needed data first.
    3160             :      */
    3161      945416 :     start_timestamp = GetCurrentStatementStartTimestamp();
    3162      945416 :     if (cmd_str != NULL)
    3163             :     {
    3164             :         /*
    3165             :          * Compute length of to-be-stored string unaware of multi-byte
    3166             :          * characters. For speed reasons that'll get corrected on read, rather
    3167             :          * than computed every write.
    3168             :          */
    3169      481614 :         len = Min(strlen(cmd_str), pgstat_track_activity_query_size - 1);
    3170             :     }
    3171      945416 :     current_timestamp = GetCurrentTimestamp();
    3172             : 
    3173             :     /*
    3174             :      * Now update the status entry
    3175             :      */
    3176      945416 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3177             : 
    3178      945416 :     beentry->st_state = state;
    3179      945416 :     beentry->st_state_start_timestamp = current_timestamp;
    3180             : 
    3181      945416 :     if (cmd_str != NULL)
    3182             :     {
    3183      481614 :         memcpy((char *) beentry->st_activity_raw, cmd_str, len);
    3184      481614 :         beentry->st_activity_raw[len] = '\0';
    3185      481614 :         beentry->st_activity_start_timestamp = start_timestamp;
    3186             :     }
    3187             : 
    3188      945416 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3189             : }
    3190             : 
    3191             : /*-----------
    3192             :  * pgstat_progress_start_command() -
    3193             :  *
    3194             :  * Set st_progress_command (and st_progress_command_target) in own backend
    3195             :  * entry.  Also, zero-initialize st_progress_param array.
    3196             :  *-----------
    3197             :  */
    3198             : void
    3199       93762 : pgstat_progress_start_command(ProgressCommandType cmdtype, Oid relid)
    3200             : {
    3201       93762 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3202             : 
    3203       93762 :     if (!beentry || !pgstat_track_activities)
    3204       37440 :         return;
    3205             : 
    3206       56322 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3207       56322 :     beentry->st_progress_command = cmdtype;
    3208       56322 :     beentry->st_progress_command_target = relid;
    3209       56322 :     MemSet(&beentry->st_progress_param, 0, sizeof(beentry->st_progress_param));
    3210       56322 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3211             : }
    3212             : 
    3213             : /*-----------
    3214             :  * pgstat_progress_update_param() -
    3215             :  *
    3216             :  * Update index'th member in st_progress_param[] of own backend entry.
    3217             :  *-----------
    3218             :  */
    3219             : void
    3220    14660514 : pgstat_progress_update_param(int index, int64 val)
    3221             : {
    3222    14660514 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3223             : 
    3224             :     Assert(index >= 0 && index < PGSTAT_NUM_PROGRESS_PARAM);
    3225             : 
    3226    14660514 :     if (!beentry || !pgstat_track_activities)
    3227     5793280 :         return;
    3228             : 
    3229     8867234 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3230     8867234 :     beentry->st_progress_param[index] = val;
    3231     8867234 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3232             : }
    3233             : 
    3234             : /*-----------
    3235             :  * pgstat_progress_update_multi_param() -
    3236             :  *
    3237             :  * Update multiple members in st_progress_param[] of own backend entry.
    3238             :  * This is atomic; readers won't see intermediate states.
    3239             :  *-----------
    3240             :  */
    3241             : void
    3242      319990 : pgstat_progress_update_multi_param(int nparam, const int *index,
    3243             :                                    const int64 *val)
    3244             : {
    3245      319990 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3246             :     int         i;
    3247             : 
    3248      319990 :     if (!beentry || !pgstat_track_activities || nparam == 0)
    3249       97280 :         return;
    3250             : 
    3251      222710 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3252             : 
    3253      826350 :     for (i = 0; i < nparam; ++i)
    3254             :     {
    3255             :         Assert(index[i] >= 0 && index[i] < PGSTAT_NUM_PROGRESS_PARAM);
    3256             : 
    3257      603640 :         beentry->st_progress_param[index[i]] = val[i];
    3258             :     }
    3259             : 
    3260      222710 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3261             : }
    3262             : 
    3263             : /*-----------
    3264             :  * pgstat_progress_end_command() -
    3265             :  *
    3266             :  * Reset st_progress_command (and st_progress_command_target) in own backend
    3267             :  * entry.  This signals the end of the command.
    3268             :  *-----------
    3269             :  */
    3270             : void
    3271      115386 : pgstat_progress_end_command(void)
    3272             : {
    3273      115386 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3274             : 
    3275      115386 :     if (!beentry)
    3276       37440 :         return;
    3277       77946 :     if (!pgstat_track_activities
    3278           0 :         && beentry->st_progress_command == PROGRESS_COMMAND_INVALID)
    3279           0 :         return;
    3280             : 
    3281       77946 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3282       77946 :     beentry->st_progress_command = PROGRESS_COMMAND_INVALID;
    3283       77946 :     beentry->st_progress_command_target = InvalidOid;
    3284       77946 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3285             : }
    3286             : 
    3287             : /* ----------
    3288             :  * pgstat_report_appname() -
    3289             :  *
    3290             :  *  Called to update our application name.
    3291             :  * ----------
    3292             :  */
    3293             : void
    3294       21156 : pgstat_report_appname(const char *appname)
    3295             : {
    3296       21156 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3297             :     int         len;
    3298             : 
    3299       21156 :     if (!beentry)
    3300        1864 :         return;
    3301             : 
    3302             :     /* This should be unnecessary if GUC did its job, but be safe */
    3303       19292 :     len = pg_mbcliplen(appname, strlen(appname), NAMEDATALEN - 1);
    3304             : 
    3305             :     /*
    3306             :      * Update my status entry, following the protocol of bumping
    3307             :      * st_changecount before and after.  We use a volatile pointer here to
    3308             :      * ensure the compiler doesn't try to get cute.
    3309             :      */
    3310       19292 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3311             : 
    3312       19292 :     memcpy((char *) beentry->st_appname, appname, len);
    3313       19292 :     beentry->st_appname[len] = '\0';
    3314             : 
    3315       19292 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3316             : }
    3317             : 
    3318             : /*
    3319             :  * Report current transaction start timestamp as the specified value.
    3320             :  * Zero means there is no active transaction.
    3321             :  */
    3322             : void
    3323      920932 : pgstat_report_xact_timestamp(TimestampTz tstamp)
    3324             : {
    3325      920932 :     volatile PgBackendStatus *beentry = MyBEEntry;
    3326             : 
    3327      920932 :     if (!pgstat_track_activities || !beentry)
    3328         640 :         return;
    3329             : 
    3330             :     /*
    3331             :      * Update my status entry, following the protocol of bumping
    3332             :      * st_changecount before and after.  We use a volatile pointer here to
    3333             :      * ensure the compiler doesn't try to get cute.
    3334             :      */
    3335      920292 :     PGSTAT_BEGIN_WRITE_ACTIVITY(beentry);
    3336             : 
    3337      920292 :     beentry->st_xact_start_timestamp = tstamp;
    3338             : 
    3339      920292 :     PGSTAT_END_WRITE_ACTIVITY(beentry);
    3340             : }
    3341             : 
    3342             : /* ----------
    3343             :  * pgstat_read_current_status() -
    3344             :  *
    3345             :  *  Copy the current contents of the PgBackendStatus array to local memory,
    3346             :  *  if not already done in this transaction.
    3347             :  * ----------
    3348             :  */
    3349             : static void
    3350        1730 : pgstat_read_current_status(void)
    3351             : {
    3352             :     volatile PgBackendStatus *beentry;
    3353             :     LocalPgBackendStatus *localtable;
    3354             :     LocalPgBackendStatus *localentry;
    3355             :     char       *localappname,
    3356             :                *localclienthostname,
    3357             :                *localactivity;
    3358             : #ifdef USE_SSL
    3359             :     PgBackendSSLStatus *localsslstatus;
    3360             : #endif
    3361             : #ifdef ENABLE_GSS
    3362             :     PgBackendGSSStatus *localgssstatus;
    3363             : #endif
    3364             :     int         i;
    3365             : 
    3366             :     Assert(!pgStatRunningInCollector);
    3367        1730 :     if (localBackendStatusTable)
    3368        1522 :         return;                 /* already done */
    3369             : 
    3370         208 :     pgstat_setup_memcxt();
    3371             : 
    3372             :     /*
    3373             :      * Allocate storage for local copy of state data.  We can presume that
    3374             :      * none of these requests overflow size_t, because we already calculated
    3375             :      * the same values using mul_size during shmem setup.  However, with
    3376             :      * probably-silly values of pgstat_track_activity_query_size and
    3377             :      * max_connections, the localactivity buffer could exceed 1GB, so use
    3378             :      * "huge" allocation for that one.
    3379             :      */
    3380         208 :     localtable = (LocalPgBackendStatus *)
    3381         208 :         MemoryContextAlloc(pgStatLocalContext,
    3382         208 :                            sizeof(LocalPgBackendStatus) * NumBackendStatSlots);
    3383         208 :     localappname = (char *)
    3384         208 :         MemoryContextAlloc(pgStatLocalContext,
    3385         208 :                            NAMEDATALEN * NumBackendStatSlots);
    3386         208 :     localclienthostname = (char *)
    3387         208 :         MemoryContextAlloc(pgStatLocalContext,
    3388         208 :                            NAMEDATALEN * NumBackendStatSlots);
    3389         208 :     localactivity = (char *)
    3390         208 :         MemoryContextAllocHuge(pgStatLocalContext,
    3391         208 :                                pgstat_track_activity_query_size * NumBackendStatSlots);
    3392             : #ifdef USE_SSL
    3393         208 :     localsslstatus = (PgBackendSSLStatus *)
    3394         208 :         MemoryContextAlloc(pgStatLocalContext,
    3395         208 :                            sizeof(PgBackendSSLStatus) * NumBackendStatSlots);
    3396             : #endif
    3397             : #ifdef ENABLE_GSS
    3398             :     localgssstatus = (PgBackendGSSStatus *)
    3399             :         MemoryContextAlloc(pgStatLocalContext,
    3400             :                            sizeof(PgBackendGSSStatus) * NumBackendStatSlots);
    3401             : #endif
    3402             : 
    3403         208 :     localNumBackends = 0;
    3404             : 
    3405         208 :     beentry = BackendStatusArray;
    3406         208 :     localentry = localtable;
    3407        8144 :     for (i = 1; i <= NumBackendStatSlots; i++)
    3408             :     {
    3409             :         /*
    3410             :          * Follow the protocol of retrying if st_changecount changes while we
    3411             :          * copy the entry, or if it's odd.  (The check for odd is needed to
    3412             :          * cover the case where we are able to completely copy the entry while
    3413             :          * the source backend is between increment steps.)  We use a volatile
    3414             :          * pointer here to ensure the compiler doesn't try to get cute.
    3415             :          */
    3416             :         for (;;)
    3417           0 :         {
    3418             :             int         before_changecount;
    3419             :             int         after_changecount;
    3420             : 
    3421        7936 :             pgstat_begin_read_activity(beentry, before_changecount);
    3422             : 
    3423        7936 :             localentry->backendStatus.st_procpid = beentry->st_procpid;
    3424             :             /* Skip all the data-copying work if entry is not in use */
    3425        7936 :             if (localentry->backendStatus.st_procpid > 0)
    3426             :             {
    3427        1522 :                 memcpy(&localentry->backendStatus, unvolatize(PgBackendStatus *, beentry), sizeof(PgBackendStatus));
    3428             : 
    3429             :                 /*
    3430             :                  * For each PgBackendStatus field that is a pointer, copy the
    3431             :                  * pointed-to data, then adjust the local copy of the pointer
    3432             :                  * field to point at the local copy of the data.
    3433             :                  *
    3434             :                  * strcpy is safe even if the string is modified concurrently,
    3435             :                  * because there's always a \0 at the end of the buffer.
    3436             :                  */
    3437        1522 :                 strcpy(localappname, (char *) beentry->st_appname);
    3438        1522 :                 localentry->backendStatus.st_appname = localappname;
    3439        1522 :                 strcpy(localclienthostname, (char *) beentry->st_clienthostname);
    3440        1522 :                 localentry->backendStatus.st_clienthostname = localclienthostname;
    3441        1522 :                 strcpy(localactivity, (char *) beentry->st_activity_raw);
    3442        1522 :                 localentry->backendStatus.st_activity_raw = localactivity;
    3443             : #ifdef USE_SSL
    3444        1522 :                 if (beentry->st_ssl)
    3445             :                 {
    3446           4 :                     memcpy(localsslstatus, beentry->st_sslstatus, sizeof(PgBackendSSLStatus));
    3447           4 :                     localentry->backendStatus.st_sslstatus = localsslstatus;
    3448             :                 }
    3449             : #endif
    3450             : #ifdef ENABLE_GSS
    3451             :                 if (beentry->st_gss)
    3452             :                 {
    3453             :                     memcpy(localgssstatus, beentry->st_gssstatus, sizeof(PgBackendGSSStatus));
    3454             :                     localentry->backendStatus.st_gssstatus = localgssstatus;
    3455             :                 }
    3456             : #endif
    3457             :             }
    3458             : 
    3459        7936 :             pgstat_end_read_activity(beentry, after_changecount);
    3460             : 
    3461        7936 :             if (pgstat_read_activity_complete(before_changecount,
    3462             :                                               after_changecount))
    3463        7936 :                 break;
    3464             : 
    3465             :             /* Make sure we can break out of loop if stuck... */
    3466           0 :             CHECK_FOR_INTERRUPTS();
    3467             :         }
    3468             : 
    3469        7936 :         beentry++;
    3470             :         /* Only valid entries get included into the local array */
    3471        7936 :         if (localentry->backendStatus.st_procpid > 0)
    3472             :         {
    3473        1522 :             BackendIdGetTransactionIds(i,
    3474             :                                        &localentry->backend_xid,
    3475             :                                        &localentry->backend_xmin);
    3476             : 
    3477        1522 :             localentry++;
    3478        1522 :             localappname += NAMEDATALEN;
    3479        1522 :             localclienthostname += NAMEDATALEN;
    3480        1522 :             localactivity += pgstat_track_activity_query_size;
    3481             : #ifdef USE_SSL
    3482        1522 :             localsslstatus++;
    3483             : #endif
    3484             : #ifdef ENABLE_GSS
    3485             :             localgssstatus++;
    3486             : #endif
    3487        1522 :             localNumBackends++;
    3488             :         }
    3489             :     }
    3490             : 
    3491             :     /* Set the pointer only after completion of a valid table */
    3492         208 :     localBackendStatusTable = localtable;
    3493             : }
    3494             : 
    3495             : /* ----------
    3496             :  * pgstat_get_wait_event_type() -
    3497             :  *
    3498             :  *  Return a string representing the current wait event type, backend is
    3499             :  *  waiting on.
    3500             :  */
    3501             : const char *
    3502        1488 : pgstat_get_wait_event_type(uint32 wait_event_info)
    3503             : {
    3504             :     uint32      classId;
    3505             :     const char *event_type;
    3506             : 
    3507             :     /* report process as not waiting. */
    3508        1488 :     if (wait_event_info == 0)
    3509         218 :         return NULL;
    3510             : 
    3511        1270 :     classId = wait_event_info & 0xFF000000;
    3512             : 
    3513        1270 :     switch (classId)
    3514             :     {
    3515             :         case PG_WAIT_LWLOCK:
    3516           0 :             event_type = "LWLock";
    3517           0 :             break;
    3518             :         case PG_WAIT_LOCK:
    3519           0 :             event_type = "Lock";
    3520           0 :             break;
    3521             :         case PG_WAIT_BUFFER_PIN:
    3522           0 :             event_type = "BufferPin";
    3523           0 :             break;
    3524             :         case PG_WAIT_ACTIVITY:
    3525        1140 :             event_type = "Activity";
    3526        1140 :             break;
    3527             :         case PG_WAIT_CLIENT:
    3528         130 :             event_type = "Client";
    3529         130 :             break;
    3530             :         case PG_WAIT_EXTENSION:
    3531           0 :             event_type = "Extension";
    3532           0 :             break;
    3533             :         case PG_WAIT_IPC:
    3534           0 :             event_type = "IPC";
    3535           0 :             break;
    3536             :         case PG_WAIT_TIMEOUT:
    3537           0 :             event_type = "Timeout";
    3538           0 :             break;
    3539             :         case PG_WAIT_IO:
    3540           0 :             event_type = "IO";
    3541           0 :             break;
    3542             :         default:
    3543           0 :             event_type = "???";
    3544           0 :             break;
    3545             :     }
    3546             : 
    3547        1270 :     return event_type;
    3548             : }
    3549             : 
    3550             : /* ----------
    3551             :  * pgstat_get_wait_event() -
    3552             :  *
    3553             :  *  Return a string representing the current wait event, backend is
    3554             :  *  waiting on.
    3555             :  */
    3556             : const char *
    3557        1488 : pgstat_get_wait_event(uint32 wait_event_info)
    3558             : {
    3559             :     uint32      classId;
    3560             :     uint16      eventId;
    3561             :     const char *event_name;
    3562             : 
    3563             :     /* report process as not waiting. */
    3564        1488 :     if (wait_event_info == 0)
    3565         218 :         return NULL;
    3566             : 
    3567        1270 :     classId = wait_event_info & 0xFF000000;
    3568        1270 :     eventId = wait_event_info & 0x0000FFFF;
    3569             : 
    3570        1270 :     switch (classId)
    3571             :     {
    3572             :         case PG_WAIT_LWLOCK:
    3573           0 :             event_name = GetLWLockIdentifier(classId, eventId);
    3574           0 :             break;
    3575             :         case PG_WAIT_LOCK:
    3576           0 :             event_name = GetLockNameFromTagType(eventId);
    3577           0 :             break;
    3578             :         case PG_WAIT_BUFFER_PIN:
    3579           0 :             event_name = "BufferPin";
    3580           0 :             break;
    3581             :         case PG_WAIT_ACTIVITY:
    3582             :             {
    3583        1140 :                 WaitEventActivity w = (WaitEventActivity) wait_event_info;
    3584             : 
    3585        1140 :                 event_name = pgstat_get_wait_activity(w);
    3586        1140 :                 break;
    3587             :             }
    3588             :         case PG_WAIT_CLIENT:
    3589             :             {
    3590         130 :                 WaitEventClient w = (WaitEventClient) wait_event_info;
    3591             : 
    3592         130 :                 event_name = pgstat_get_wait_client(w);
    3593         130 :                 break;
    3594             :             }
    3595             :         case PG_WAIT_EXTENSION:
    3596           0 :             event_name = "Extension";
    3597           0 :             break;
    3598             :         case PG_WAIT_IPC:
    3599             :             {
    3600           0 :                 WaitEventIPC w = (WaitEventIPC) wait_event_info;
    3601             : 
    3602           0 :                 event_name = pgstat_get_wait_ipc(w);
    3603           0 :                 break;
    3604             :             }
    3605             :         case PG_WAIT_TIMEOUT:
    3606             :             {
    3607           0 :                 WaitEventTimeout w = (WaitEventTimeout) wait_event_info;
    3608             : 
    3609           0 :                 event_name = pgstat_get_wait_timeout(w);
    3610           0 :                 break;
    3611             :             }
    3612             :         case PG_WAIT_IO:
    3613             :             {
    3614           0 :                 WaitEventIO w = (WaitEventIO) wait_event_info;
    3615             : 
    3616           0 :                 event_name = pgstat_get_wait_io(w);
    3617           0 :                 break;
    3618             :             }
    3619             :         default:
    3620           0 :             event_name = "unknown wait event";
    3621           0 :             break;
    3622             :     }
    3623             : 
    3624        1270 :     return event_name;
    3625             : }
    3626             : 
    3627             : /* ----------
    3628             :  * pgstat_get_wait_activity() -
    3629             :  *
    3630             :  * Convert WaitEventActivity to string.
    3631             :  * ----------
    3632             :  */
    3633             : static const char *
    3634        1140 : pgstat_get_wait_activity(WaitEventActivity w)
    3635             : {
    3636        1140 :     const char *event_name = "unknown wait event";
    3637             : 
    3638        1140 :     switch (w)
    3639             :     {
    3640             :         case WAIT_EVENT_ARCHIVER_MAIN:
    3641           0 :             event_name = "ArchiverMain";
    3642           0 :             break;
    3643             :         case WAIT_EVENT_AUTOVACUUM_MAIN:
    3644         190 :             event_name = "AutoVacuumMain";
    3645         190 :             break;
    3646             :         case WAIT_EVENT_BGWRITER_HIBERNATE:
    3647          10 :             event_name = "BgWriterHibernate";
    3648          10 :             break;
    3649             :         case WAIT_EVENT_BGWRITER_MAIN:
    3650         192 :             event_name = "BgWriterMain";
    3651         192 :             break;
    3652             :         case WAIT_EVENT_CHECKPOINTER_MAIN:
    3653         196 :             event_name = "CheckpointerMain";
    3654         196 :             break;
    3655             :         case WAIT_EVENT_LOGICAL_APPLY_MAIN:
    3656           0 :             event_name = "LogicalApplyMain";
    3657           0 :             break;
    3658             :         case WAIT_EVENT_LOGICAL_LAUNCHER_MAIN:
    3659         194 :             event_name = "LogicalLauncherMain";
    3660         194 :             break;
    3661             :         case WAIT_EVENT_PGSTAT_MAIN:
    3662           0 :             event_name = "PgStatMain";
    3663           0 :             break;
    3664             :         case WAIT_EVENT_RECOVERY_WAL_ALL:
    3665           8 :             event_name = "RecoveryWalAll";
    3666           8 :             break;
    3667             :         case WAIT_EVENT_RECOVERY_WAL_STREAM:
    3668           0 :             event_name = "RecoveryWalStream";
    3669           0 :             break;
    3670             :         case WAIT_EVENT_SYSLOGGER_MAIN:
    3671           0 :             event_name = "SysLoggerMain";
    3672           0 :             break;
    3673             :         case WAIT_EVENT_WAL_RECEIVER_MAIN:
    3674           8 :             event_name = "WalReceiverMain";
    3675           8 :             break;
    3676             :         case WAIT_EVENT_WAL_SENDER_MAIN:
    3677         148 :             event_name = "WalSenderMain";
    3678         148 :             break;
    3679             :         case WAIT_EVENT_WAL_WRITER_MAIN:
    3680         194 :             event_name = "WalWriterMain";
    3681         194 :             break;
    3682             :             /* no default case, so that compiler will warn */
    3683             :     }
    3684             : 
    3685        1140 :     return event_name;
    3686             : }
    3687             : 
    3688             : /* ----------
    3689             :  * pgstat_get_wait_client() -
    3690             :  *
    3691             :  * Convert WaitEventClient to string.
    3692             :  * ----------
    3693             :  */
    3694             : static const char *
    3695         130 : pgstat_get_wait_client(WaitEventClient w)
    3696             : {
    3697         130 :     const char *event_name = "unknown wait event";
    3698             : 
    3699         130 :     switch (w)
    3700             :     {
    3701             :         case WAIT_EVENT_CLIENT_READ:
    3702           0 :             event_name = "ClientRead";
    3703           0 :             break;
    3704             :         case WAIT_EVENT_CLIENT_WRITE:
    3705           0 :             event_name = "ClientWrite";
    3706           0 :             break;
    3707             :         case WAIT_EVENT_LIBPQWALRECEIVER_CONNECT:
    3708           0 :             event_name = "LibPQWalReceiverConnect";
    3709           0 :             break;
    3710             :         case WAIT_EVENT_LIBPQWALRECEIVER_RECEIVE:
    3711           0 :             event_name = "LibPQWalReceiverReceive";
    3712           0 :             break;
    3713             :         case WAIT_EVENT_SSL_OPEN_SERVER:
    3714           0 :             event_name = "SSLOpenServer";
    3715           0 :             break;
    3716             :         case WAIT_EVENT_WAL_RECEIVER_WAIT_START:
    3717           0 :             event_name = "WalReceiverWaitStart";
    3718           0 :             break;
    3719             :         case WAIT_EVENT_WAL_SENDER_WAIT_WAL:
    3720         130 :             event_name = "WalSenderWaitForWAL";
    3721         130 :             break;
    3722             :         case WAIT_EVENT_WAL_SENDER_WRITE_DATA:
    3723           0 :             event_name = "WalSenderWriteData";
    3724           0 :             break;
    3725             :         case WAIT_EVENT_GSS_OPEN_SERVER:
    3726           0 :             event_name = "GSSOpenServer";
    3727           0 :             break;
    3728             :             /* no default case, so that compiler will warn */
    3729             :     }
    3730             : 
    3731         130 :     return event_name;
    3732             : }
    3733             : 
    3734             : /* ----------
    3735             :  * pgstat_get_wait_ipc() -
    3736             :  *
    3737             :  * Convert WaitEventIPC to string.
    3738             :  * ----------
    3739             :  */
    3740             : static const char *
    3741           0 : pgstat_get_wait_ipc(WaitEventIPC w)
    3742             : {
    3743           0 :     const char *event_name = "unknown wait event";
    3744             : 
    3745           0 :     switch (w)
    3746             :     {
    3747             :         case WAIT_EVENT_BGWORKER_SHUTDOWN:
    3748           0 :             event_name = "BgWorkerShutdown";
    3749           0 :             break;
    3750             :         case WAIT_EVENT_BGWORKER_STARTUP:
    3751           0 :             event_name = "BgWorkerStartup";
    3752           0 :             break;
    3753             :         case WAIT_EVENT_BTREE_PAGE:
    3754           0 :             event_name = "BtreePage";
    3755           0 :             break;
    3756             :         case WAIT_EVENT_CHECKPOINT_DONE:
    3757           0 :             event_name = "CheckpointDone";
    3758           0 :             break;
    3759             :         case WAIT_EVENT_CHECKPOINT_START:
    3760           0 :             event_name = "CheckpointStart";
    3761           0 :             break;
    3762             :         case WAIT_EVENT_CLOG_GROUP_UPDATE:
    3763           0 :             event_name = "ClogGroupUpdate";
    3764           0 :             break;
    3765             :         case WAIT_EVENT_EXECUTE_GATHER:
    3766           0 :             event_name = "ExecuteGather";
    3767           0 :             break;
    3768             :         case WAIT_EVENT_HASH_BATCH_ALLOCATING:
    3769           0 :             event_name = "Hash/Batch/Allocating";
    3770           0 :             break;
    3771             :         case WAIT_EVENT_HASH_BATCH_ELECTING:
    3772           0 :             event_name = "Hash/Batch/Electing";
    3773           0 :             break;
    3774             :         case WAIT_EVENT_HASH_BATCH_LOADING:
    3775           0 :             event_name = "Hash/Batch/Loading";
    3776           0 :             break;
    3777             :         case WAIT_EVENT_HASH_BUILD_ALLOCATING:
    3778           0 :             event_name = "Hash/Build/Allocating";
    3779           0 :             break;
    3780             :         case WAIT_EVENT_HASH_BUILD_ELECTING:
    3781           0 :             event_name = "Hash/Build/Electing";
    3782           0 :             break;
    3783             :         case WAIT_EVENT_HASH_BUILD_HASHING_INNER:
    3784           0 :             event_name = "Hash/Build/HashingInner";
    3785           0 :             break;
    3786             :         case WAIT_EVENT_HASH_BUILD_HASHING_OUTER:
    3787           0 :             event_name = "Hash/Build/HashingOuter";
    3788           0 :             break;
    3789             :         case WAIT_EVENT_HASH_GROW_BATCHES_ALLOCATING:
    3790           0 :             event_name = "Hash/GrowBatches/Allocating";
    3791           0 :             break;
    3792             :         case WAIT_EVENT_HASH_GROW_BATCHES_DECIDING:
    3793           0 :             event_name = "Hash/GrowBatches/Deciding";
    3794           0 :             break;
    3795             :         case WAIT_EVENT_HASH_GROW_BATCHES_ELECTING:
    3796           0 :             event_name = "Hash/GrowBatches/Electing";
    3797           0 :             break;
    3798             :         case WAIT_EVENT_HASH_GROW_BATCHES_FINISHING:
    3799           0 :             event_name = "Hash/GrowBatches/Finishing";
    3800           0 :             break;
    3801             :         case WAIT_EVENT_HASH_GROW_BATCHES_REPARTITIONING:
    3802           0 :             event_name = "Hash/GrowBatches/Repartitioning";
    3803           0 :             break;
    3804             :         case WAIT_EVENT_HASH_GROW_BUCKETS_ALLOCATING:
    3805           0 :             event_name = "Hash/GrowBuckets/Allocating";
    3806           0 :             break;
    3807             :         case WAIT_EVENT_HASH_GROW_BUCKETS_ELECTING:
    3808           0 :             event_name = "Hash/GrowBuckets/Electing";
    3809           0 :             break;
    3810             :         case WAIT_EVENT_HASH_GROW_BUCKETS_REINSERTING:
    3811           0 :             event_name = "Hash/GrowBuckets/Reinserting";
    3812           0 :             break;
    3813             :         case WAIT_EVENT_LOGICAL_SYNC_DATA:
    3814           0 :             event_name = "LogicalSyncData";
    3815           0 :             break;
    3816             :         case WAIT_EVENT_LOGICAL_SYNC_STATE_CHANGE:
    3817           0 :             event_name = "LogicalSyncStateChange";
    3818           0 :             break;
    3819             :         case WAIT_EVENT_MQ_INTERNAL:
    3820           0 :             event_name = "MessageQueueInternal";
    3821           0 :             break;
    3822             :         case WAIT_EVENT_MQ_PUT_MESSAGE:
    3823           0 :             event_name = "MessageQueuePutMessage";
    3824           0 :             break;
    3825             :         case WAIT_EVENT_MQ_RECEIVE:
    3826           0 :             event_name = "MessageQueueReceive";
    3827           0 :             break;
    3828             :         case WAIT_EVENT_MQ_SEND:
    3829           0 :             event_name = "MessageQueueSend";
    3830           0 :             break;
    3831             :         case WAIT_EVENT_PARALLEL_BITMAP_SCAN:
    3832           0 :             event_name = "ParallelBitmapScan";
    3833           0 :             break;
    3834             :         case WAIT_EVENT_PARALLEL_CREATE_INDEX_SCAN:
    3835           0 :             event_name = "ParallelCreateIndexScan";
    3836           0 :             break;
    3837             :         case WAIT_EVENT_PARALLEL_FINISH:
    3838           0 :             event_name = "ParallelFinish";
    3839           0 :             break;
    3840             :         case WAIT_EVENT_PROCARRAY_GROUP_UPDATE:
    3841           0 :             event_name = "ProcArrayGroupUpdate";
    3842           0 :             break;
    3843             :         case WAIT_EVENT_PROMOTE:
    3844           0 :             event_name = "Promote";
    3845           0 :             break;
    3846             :         case WAIT_EVENT_REPLICATION_ORIGIN_DROP:
    3847           0 :             event_name = "ReplicationOriginDrop";
    3848           0 :             break;
    3849             :         case WAIT_EVENT_REPLICATION_SLOT_DROP:
    3850           0 :             event_name = "ReplicationSlotDrop";
    3851           0 :             break;
    3852             :         case WAIT_EVENT_SAFE_SNAPSHOT:
    3853           0 :             event_name = "SafeSnapshot";
    3854           0 :             break;
    3855             :         case WAIT_EVENT_SYNC_REP:
    3856           0 :             event_name = "SyncRep";
    3857           0 :             break;
    3858             :             /* no default case, so that compiler will warn */
    3859             :     }
    3860             : 
    3861           0 :     return event_name;
    3862             : }
    3863             : 
    3864             : /* ----------
    3865             :  * pgstat_get_wait_timeout() -
    3866             :  *
    3867             :  * Convert WaitEventTimeout to string.
    3868             :  * ----------
    3869             :  */
    3870             : static const char *
    3871           0 : pgstat_get_wait_timeout(WaitEventTimeout w)
    3872             : {
    3873           0 :     const char *event_name = "unknown wait event";
    3874             : 
    3875           0 :     switch (w)
    3876             :     {
    3877             :         case WAIT_EVENT_BASE_BACKUP_THROTTLE:
    3878           0 :             event_name = "BaseBackupThrottle";
    3879           0 :             break;
    3880             :         case WAIT_EVENT_PG_SLEEP:
    3881           0 :             event_name = "PgSleep";
    3882           0 :             break;
    3883             :         case WAIT_EVENT_RECOVERY_APPLY_DELAY:
    3884           0 :             event_name = "RecoveryApplyDelay";
    3885           0 :             break;
    3886             :             /* no default case, so that compiler will warn */
    3887             :     }
    3888             : 
    3889           0 :     return event_name;
    3890             : }
    3891             : 
    3892             : /* ----------
    3893             :  * pgstat_get_wait_io() -
    3894             :  *
    3895             :  * Convert WaitEventIO to string.
    3896             :  * ----------
    3897             :  */
    3898             : static const char *
    3899           0 : pgstat_get_wait_io(WaitEventIO w)
    3900             : {
    3901           0 :     const char *event_name = "unknown wait event";
    3902             : 
    3903           0 :     switch (w)
    3904             :     {
    3905             :         case WAIT_EVENT_BUFFILE_READ:
    3906           0 :             event_name = "BufFileRead";
    3907           0 :             break;
    3908             :         case WAIT_EVENT_BUFFILE_WRITE:
    3909           0 :             event_name = "BufFileWrite";
    3910           0 :             break;
    3911             :         case WAIT_EVENT_CONTROL_FILE_READ:
    3912           0 :             event_name = "ControlFileRead";
    3913           0 :             break;
    3914             :         case WAIT_EVENT_CONTROL_FILE_SYNC:
    3915           0 :             event_name = "ControlFileSync";
    3916           0 :             break;
    3917             :         case WAIT_EVENT_CONTROL_FILE_SYNC_UPDATE:
    3918           0 :             event_name = "ControlFileSyncUpdate";
    3919           0 :             break;
    3920             :         case WAIT_EVENT_CONTROL_FILE_WRITE:
    3921           0 :             event_name = "ControlFileWrite";
    3922           0 :             break;
    3923             :         case WAIT_EVENT_CONTROL_FILE_WRITE_UPDATE:
    3924           0 :             event_name = "ControlFileWriteUpdate";
    3925           0 :             break;
    3926             :         case WAIT_EVENT_COPY_FILE_READ:
    3927           0 :             event_name = "CopyFileRead";
    3928           0 :             break;
    3929             :         case WAIT_EVENT_COPY_FILE_WRITE:
    3930           0 :             event_name = "CopyFileWrite";
    3931           0 :             break;
    3932             :         case WAIT_EVENT_DATA_FILE_EXTEND:
    3933           0 :             event_name = "DataFileExtend";
    3934           0 :             break;
    3935             :         case WAIT_EVENT_DATA_FILE_FLUSH:
    3936           0 :             event_name = "DataFileFlush";
    3937           0 :             break;
    3938             :         case WAIT_EVENT_DATA_FILE_IMMEDIATE_SYNC:
    3939           0 :             event_name = "DataFileImmediateSync";
    3940           0 :             break;
    3941             :         case WAIT_EVENT_DATA_FILE_PREFETCH:
    3942           0 :             event_name = "DataFilePrefetch";
    3943           0 :             break;
    3944             :         case WAIT_EVENT_DATA_FILE_READ:
    3945           0 :             event_name = "DataFileRead";
    3946           0 :             break;
    3947             :         case WAIT_EVENT_DATA_FILE_SYNC:
    3948           0 :             event_name = "DataFileSync";
    3949           0 :             break;
    3950             :         case WAIT_EVENT_DATA_FILE_TRUNCATE:
    3951           0 :             event_name = "DataFileTruncate";
    3952           0 :             break;
    3953             :         case WAIT_EVENT_DATA_FILE_WRITE:
    3954           0 :             event_name = "DataFileWrite";
    3955           0 :             break;
    3956             :         case WAIT_EVENT_DSM_FILL_ZERO_WRITE:
    3957           0 :             event_name = "DSMFillZeroWrite";
    3958           0 :             break;
    3959             :         case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_READ:
    3960           0 :             event_name = "LockFileAddToDataDirRead";
    3961           0 :             break;
    3962             :         case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_SYNC:
    3963           0 :             event_name = "LockFileAddToDataDirSync";
    3964           0 :             break;
    3965             :         case WAIT_EVENT_LOCK_FILE_ADDTODATADIR_WRITE:
    3966           0 :             event_name = "LockFileAddToDataDirWrite";
    3967           0 :             break;
    3968             :         case WAIT_EVENT_LOCK_FILE_CREATE_READ:
    3969           0 :             event_name = "LockFileCreateRead";
    3970           0 :             break;
    3971             :         case WAIT_EVENT_LOCK_FILE_CREATE_SYNC:
    3972           0 :             event_name = "LockFileCreateSync";
    3973           0 :             break;
    3974             :         case WAIT_EVENT_LOCK_FILE_CREATE_WRITE:
    3975           0 :             event_name = "LockFileCreateWrite";
    3976           0 :             break;
    3977             :         case WAIT_EVENT_LOCK_FILE_RECHECKDATADIR_READ:
    3978           0 :             event_name = "LockFileReCheckDataDirRead";
    3979           0 :             break;
    3980             :         case WAIT_EVENT_LOGICAL_REWRITE_CHECKPOINT_SYNC:
    3981           0 :             event_name = "LogicalRewriteCheckpointSync";
    3982           0 :             break;
    3983             :         case WAIT_EVENT_LOGICAL_REWRITE_MAPPING_SYNC:
    3984           0 :             event_name = "LogicalRewriteMappingSync";
    3985           0 :             break;
    3986             :         case WAIT_EVENT_LOGICAL_REWRITE_MAPPING_WRITE:
    3987           0 :             event_name = "LogicalRewriteMappingWrite";
    3988           0 :             break;
    3989             :         case WAIT_EVENT_LOGICAL_REWRITE_SYNC:
    3990           0 :             event_name = "LogicalRewriteSync";
    3991           0 :             break;
    3992             :         case WAIT_EVENT_LOGICAL_REWRITE_TRUNCATE:
    3993           0 :             event_name = "LogicalRewriteTruncate";
    3994           0 :             break;
    3995             :         case WAIT_EVENT_LOGICAL_REWRITE_WRITE:
    3996           0 :             event_name = "LogicalRewriteWrite";
    3997           0 :             break;
    3998             :         case WAIT_EVENT_RELATION_MAP_READ:
    3999           0 :             event_name = "RelationMapRead";
    4000           0 :             break;
    4001             :         case WAIT_EVENT_RELATION_MAP_SYNC:
    4002           0 :             event_name = "RelationMapSync";
    4003           0 :             break;
    4004             :         case WAIT_EVENT_RELATION_MAP_WRITE:
    4005           0 :             event_name = "RelationMapWrite";
    4006           0 :             break;
    4007             :         case WAIT_EVENT_REORDER_BUFFER_READ:
    4008           0 :             event_name = "ReorderBufferRead";
    4009           0 :             break;
    4010             :         case WAIT_EVENT_REORDER_BUFFER_WRITE:
    4011           0 :             event_name = "ReorderBufferWrite";
    4012           0 :             break;
    4013             :         case WAIT_EVENT_REORDER_LOGICAL_MAPPING_READ:
    4014           0 :             event_name = "ReorderLogicalMappingRead";
    4015           0 :             break;
    4016             :         case WAIT_EVENT_REPLICATION_SLOT_READ:
    4017           0 :             event_name = "ReplicationSlotRead";
    4018           0 :             break;
    4019             :         case WAIT_EVENT_REPLICATION_SLOT_RESTORE_SYNC:
    4020           0 :             event_name = "ReplicationSlotRestoreSync";
    4021           0 :             break;
    4022             :         case WAIT_EVENT_REPLICATION_SLOT_SYNC:
    4023           0 :             event_name = "ReplicationSlotSync";
    4024           0 :             break;
    4025             :         case WAIT_EVENT_REPLICATION_SLOT_WRITE:
    4026           0 :             event_name = "ReplicationSlotWrite";
    4027           0 :             break;
    4028             :         case WAIT_EVENT_SLRU_FLUSH_SYNC:
    4029           0 :             event_name = "SLRUFlushSync";
    4030           0 :             break;
    4031             :         case WAIT_EVENT_SLRU_READ:
    4032           0 :             event_name = "SLRURead";
    4033           0 :             break;
    4034             :         case WAIT_EVENT_SLRU_SYNC:
    4035           0 :             event_name = "SLRUSync";
    4036           0 :             break;
    4037             :         case WAIT_EVENT_SLRU_WRITE:
    4038           0 :             event_name = "SLRUWrite";
    4039           0 :             break;
    4040             :         case WAIT_EVENT_SNAPBUILD_READ:
    4041           0 :             event_name = "SnapbuildRead";
    4042           0 :             break;
    4043             :         case WAIT_EVENT_SNAPBUILD_SYNC:
    4044           0 :             event_name = "SnapbuildSync";
    4045           0 :             break;
    4046             :         case WAIT_EVENT_SNAPBUILD_WRITE:
    4047           0 :             event_name = "SnapbuildWrite";
    4048           0 :             break;
    4049             :         case WAIT_EVENT_TIMELINE_HISTORY_FILE_SYNC:
    4050           0 :             event_name = "TimelineHistoryFileSync";
    4051           0 :             break;
    4052             :         case WAIT_EVENT_TIMELINE_HISTORY_FILE_WRITE:
    4053           0 :             event_name = "TimelineHistoryFileWrite";
    4054           0 :             break;
    4055             :         case WAIT_EVENT_TIMELINE_HISTORY_READ:
    4056           0 :             event_name = "TimelineHistoryRead";
    4057           0 :             break;
    4058             :         case WAIT_EVENT_TIMELINE_HISTORY_SYNC:
    4059           0 :             event_name = "TimelineHistorySync";
    4060           0 :             break;
    4061             :         case WAIT_EVENT_TIMELINE_HISTORY_WRITE:
    4062           0 :             event_name = "TimelineHistoryWrite";
    4063           0 :             break;
    4064             :         case WAIT_EVENT_TWOPHASE_FILE_READ:
    4065           0 :             event_name = "TwophaseFileRead";
    4066           0 :             break;
    4067             :         case WAIT_EVENT_TWOPHASE_FILE_SYNC:
    4068           0 :             event_name = "TwophaseFileSync";
    4069           0 :             break;
    4070             :         case WAIT_EVENT_TWOPHASE_FILE_WRITE:
    4071           0 :             event_name = "TwophaseFileWrite";
    4072           0 :             break;
    4073             :         case WAIT_EVENT_WALSENDER_TIMELINE_HISTORY_READ:
    4074           0 :             event_name = "WALSenderTimelineHistoryRead";
    4075           0 :             break;
    4076             :         case WAIT_EVENT_WAL_BOOTSTRAP_SYNC:
    4077           0 :             event_name = "WALBootstrapSync";
    4078           0 :             break;
    4079             :         case WAIT_EVENT_WAL_BOOTSTRAP_WRITE:
    4080           0 :             event_name = "WALBootstrapWrite";
    4081           0 :             break;
    4082             :         case WAIT_EVENT_WAL_COPY_READ:
    4083           0 :             event_name = "WALCopyRead";
    4084           0 :             break;
    4085             :         case WAIT_EVENT_WAL_COPY_SYNC:
    4086           0 :             event_name = "WALCopySync";
    4087           0 :             break;
    4088             :         case WAIT_EVENT_WAL_COPY_WRITE:
    4089           0 :             event_name = "WALCopyWrite";
    4090           0 :             break;
    4091             :         case WAIT_EVENT_WAL_INIT_SYNC:
    4092           0 :             event_name = "WALInitSync";
    4093           0 :             break;
    4094             :         case WAIT_EVENT_WAL_INIT_WRITE:
    4095           0 :             event_name = "WALInitWrite";
    4096           0 :             break;
    4097             :         case WAIT_EVENT_WAL_READ:
    4098           0 :             event_name = "WALRead";
    4099           0 :             break;
    4100             :         case WAIT_EVENT_WAL_SYNC:
    4101           0 :             event_name = "WALSync";
    4102           0 :             break;
    4103             :         case WAIT_EVENT_WAL_SYNC_METHOD_ASSIGN:
    4104           0 :             event_name = "WALSyncMethodAssign";
    4105           0 :             break;
    4106             :         case WAIT_EVENT_WAL_WRITE:
    4107           0 :             event_name = "WALWrite";
    4108           0 :             break;
    4109             : 
    4110             :             /* no default case, so that compiler will warn */
    4111             :     }
    4112             : 
    4113           0 :     return event_name;
    4114             : }
    4115             : 
    4116             : 
    4117             : /* ----------
    4118             :  * pgstat_get_backend_current_activity() -
    4119             :  *
    4120             :  *  Return a string representing the current activity of the backend with
    4121             :  *  the specified PID.  This looks directly at the BackendStatusArray,
    4122             :  *  and so will provide current information regardless of the age of our
    4123             :  *  transaction's snapshot of the status array.
    4124             :  *
    4125             :  *  It is the caller's responsibility to invoke this only for backends whose
    4126             :  *  state is expected to remain stable while the result is in use.  The
    4127             :  *  only current use is in deadlock reporting, where we can expect that
    4128             :  *  the target backend is blocked on a lock.  (There are corner cases
    4129             :  *  where the target's wait could get aborted while we are looking at it,
    4130             :  *  but the very worst consequence is to return a pointer to a string
    4131             :  *  that's been changed, so we won't worry too much.)
    4132             :  *
    4133             :  *  Note: return strings for special cases match pg_stat_get_backend_activity.
    4134             :  * ----------
    4135             :  */
    4136             : const char *
    4137          20 : pgstat_get_backend_current_activity(int pid, bool checkUser)
    4138             : {
    4139             :     PgBackendStatus *beentry;
    4140             :     int         i;
    4141             : 
    4142          20 :     beentry = BackendStatusArray;
    4143         138 :     for (i = 1; i <= MaxBackends; i++)
    4144             :     {
    4145             :         /*
    4146             :          * Although we expect the target backend's entry to be stable, that
    4147             :          * doesn't imply that anyone else's is.  To avoid identifying the
    4148             :          * wrong backend, while we check for a match to the desired PID we
    4149             :          * must follow the protocol of retrying if st_changecount changes
    4150             :          * while we examine the entry, or if it's odd.  (This might be
    4151             :          * unnecessary, since fetching or storing an int is almost certainly
    4152             :          * atomic, but let's play it safe.)  We use a volatile pointer here to
    4153             :          * ensure the compiler doesn't try to get cute.
    4154             :          */
    4155         138 :         volatile PgBackendStatus *vbeentry = beentry;
    4156             :         bool        found;
    4157             : 
    4158             :         for (;;)
    4159           0 :         {
    4160             :             int         before_changecount;
    4161             :             int         after_changecount;
    4162             : 
    4163         138 :             pgstat_begin_read_activity(vbeentry, before_changecount);
    4164             : 
    4165         138 :             found = (vbeentry->st_procpid == pid);
    4166             : 
    4167         138 :             pgstat_end_read_activity(vbeentry, after_changecount);
    4168             : 
    4169         138 :             if (pgstat_read_activity_complete(before_changecount,
    4170             :                                               after_changecount))
    4171         138 :                 break;
    4172             : 
    4173             :             /* Make sure we can break out of loop if stuck... */
    4174           0 :             CHECK_FOR_INTERRUPTS();
    4175             :         }
    4176             : 
    4177         138 :         if (found)
    4178             :         {
    4179             :             /* Now it is safe to use the non-volatile pointer */
    4180          20 :             if (checkUser && !superuser() && beentry->st_userid != GetUserId())
    4181           0 :                 return "<insufficient privilege>";
    4182          20 :             else if (*(beentry->st_activity_raw) == '\0')
    4183           0 :                 return "<command string not enabled>";
    4184             :             else
    4185             :             {
    4186             :                 /* this'll leak a bit of memory, but that seems acceptable */
    4187          20 :                 return pgstat_clip_activity(beentry->st_activity_raw);
    4188             :             }
    4189             :         }
    4190             : 
    4191         118 :         beentry++;
    4192             :     }
    4193             : 
    4194             :     /* If we get here, caller is in error ... */
    4195           0 :     return "<backend information not available>";
    4196             : }
    4197             : 
    4198             : /* ----------
    4199             :  * pgstat_get_crashed_backend_activity() -
    4200             :  *
    4201             :  *  Return a string representing the current activity of the backend with
    4202             :  *  the specified PID.  Like the function above, but reads shared memory with
    4203             :  *  the expectation that it may be corrupt.  On success, copy the string
    4204             :  *  into the "buffer" argument and return that pointer.  On failure,
    4205             :  *  return NULL.
    4206             :  *
    4207             :  *  This function is only intended to be used by the postmaster to report the
    4208             :  *  query that crashed a backend.  In particular, no attempt is made to
    4209             :  *  follow the correct concurrency protocol when accessing the
    4210             :  *  BackendStatusArray.  But that's OK, in the worst case we'll return a
    4211             :  *  corrupted message.  We also must take care not to trip on ereport(ERROR).
    4212             :  * ----------
    4213             :  */
    4214             : const char *
    4215         738 : pgstat_get_crashed_backend_activity(int pid, char *buffer, int buflen)
    4216             : {
    4217             :     volatile PgBackendStatus *beentry;
    4218             :     int         i;
    4219             : 
    4220         738 :     beentry = BackendStatusArray;
    4221             : 
    4222             :     /*
    4223             :      * We probably shouldn't get here before shared memory has been set up,
    4224             :      * but be safe.
    4225             :      */
    4226         738 :     if (beentry == NULL || BackendActivityBuffer == NULL)
    4227           0 :         return NULL;
    4228             : 
    4229       57138 :     for (i = 1; i <= MaxBackends; i++)
    4230             :     {
    4231       56458 :         if (beentry->st_procpid == pid)
    4232             :         {
    4233             :             /* Read pointer just once, so it can't change after validation */
    4234          58 :             const char *activity = beentry->st_activity_raw;
    4235             :             const char *activity_last;
    4236             : 
    4237             :             /*
    4238             :              * We mustn't access activity string before we verify that it
    4239             :              * falls within the BackendActivityBuffer. To make sure that the
    4240             :              * entire string including its ending is contained within the
    4241             :              * buffer, subtract one activity length from the buffer size.
    4242             :              */
    4243          58 :             activity_last = BackendActivityBuffer + BackendActivityBufferSize
    4244          58 :                 - pgstat_track_activity_query_size;
    4245             : 
    4246          58 :             if (activity < BackendActivityBuffer ||
    4247             :                 activity > activity_last)
    4248           0 :                 return NULL;
    4249             : 
    4250             :             /* If no string available, no point in a report */
    4251          58 :             if (activity[0] == '\0')
    4252          42 :                 return NULL;
    4253             : 
    4254             :             /*
    4255             :              * Copy only ASCII-safe characters so we don't run into encoding
    4256             :              * problems when reporting the message; and be sure not to run off
    4257             :              * the end of memory.  As only ASCII characters are reported, it
    4258             :              * doesn't seem necessary to perform multibyte aware clipping.
    4259             :              */
    4260          16 :             ascii_safe_strlcpy(buffer, activity,
    4261          16 :                                Min(buflen, pgstat_track_activity_query_size));
    4262             : 
    4263          16 :             return buffer;
    4264             :         }
    4265             : 
    4266       56400 :         beentry++;
    4267             :     }
    4268             : 
    4269             :     /* PID not found */
    4270         680 :     return NULL;
    4271             : }
    4272             : 
    4273             : const char *
    4274        4002 : pgstat_get_backend_desc(BackendType backendType)
    4275             : {
    4276        4002 :     const char *backendDesc = "unknown process type";
    4277             : 
    4278        4002 :     switch (backendType)
    4279             :     {
    4280             :         case B_AUTOVAC_LAUNCHER:
    4281         538 :             backendDesc = "autovacuum launcher";
    4282         538 :             break;
    4283             :         case B_AUTOVAC_WORKER:
    4284          64 :             backendDesc = "autovacuum worker";
    4285          64 :             break;
    4286             :         case B_BACKEND:
    4287         210 :             backendDesc = "client backend";
    4288         210 :             break;
    4289             :         case B_BG_WORKER:
    4290           0 :             backendDesc = "background worker";
    4291           0 :             break;
    4292             :         case B_BG_WRITER:
    4293         584 :             backendDesc = "background writer";
    4294         584 :             break;
    4295             :         case B_CHECKPOINTER:
    4296         584 :             backendDesc = "checkpointer";
    4297         584 :             break;
    4298             :         case B_STARTUP:
    4299         530 :             backendDesc = "startup";
    4300         530 :             break;
    4301             :         case B_WAL_RECEIVER:
    4302         190 :             backendDesc = "walreceiver";
    4303         190 :             break;
    4304             :         case B_WAL_SENDER:
    4305         748 :             backendDesc = "walsender";
    4306         748 :             break;
    4307             :         case B_WAL_WRITER:
    4308         554 :             backendDesc = "walwriter";
    4309         554 :             break;
    4310             :     }
    4311             : 
    4312        4002 :     return backendDesc;
    4313             : }
    4314             : 
    4315             : /* ------------------------------------------------------------
    4316             :  * Local support functions follow
    4317             :  * ------------------------------------------------------------
    4318             :  */
    4319             : 
    4320             : 
    4321             : /* ----------
    4322             :  * pgstat_setheader() -
    4323             :  *
    4324             :  *      Set common header fields in a statistics message
    4325             :  * ----------
    4326             :  */
    4327             : static void
    4328      100460 : pgstat_setheader(PgStat_MsgHdr *hdr, StatMsgType mtype)
    4329             : {
    4330      100460 :     hdr->m_type = mtype;
    4331      100460 : }
    4332             : 
    4333             : 
    4334             : /* ----------
    4335             :  * pgstat_send() -
    4336             :  *
    4337             :  *      Send out one statistics message to the collector
    4338             :  * ----------
    4339             :  */
    4340             : static void
    4341      100460 : pgstat_send(void *msg, int len)
    4342             : {
    4343             :     int         rc;
    4344             : 
    4345      100460 :     if (pgStatSock == PGINVALID_SOCKET)
    4346           0 :         return;
    4347             : 
    4348      100460 :     ((PgStat_MsgHdr *) msg)->m_size = len;
    4349             : 
    4350             :     /* We'll retry after EINTR, but ignore all other failures */
    4351             :     do
    4352             :     {
    4353      100460 :         rc = send(pgStatSock, msg, len, 0);
    4354      100460 :     } while (rc < 0 && errno == EINTR);
    4355             : 
    4356             : #ifdef USE_ASSERT_CHECKING
    4357             :     /* In debug builds, log send failures ... */
    4358             :     if (rc < 0)
    4359             :         elog(LOG, "could not send to statistics collector: %m");
    4360             : #endif
    4361             : }
    4362             : 
    4363             : /* ----------
    4364             :  * pgstat_send_archiver() -
    4365             :  *
    4366             :  *  Tell the collector about the WAL file that we successfully
    4367             :  *  archived or failed to archive.
    4368             :  * ----------
    4369             :  */
    4370             : void
    4371          26 : pgstat_send_archiver(const char *xlog, bool failed)
    4372             : {
    4373             :     PgStat_MsgArchiver msg;
    4374             : 
    4375             :     /*
    4376             :      * Prepare and send the message
    4377             :      */
    4378          26 :     pgstat_setheader(&msg.m_hdr, PGSTAT_MTYPE_ARCHIVER);
    4379          26 :     msg.m_failed = failed;
    4380          26 :     StrNCpy(msg.m_xlog, xlog, sizeof(msg.m_xlog));
    4381          26 :     msg.m_timestamp = GetCurrentTimestamp();
    4382          26 :     pgstat_send(&msg, sizeof(msg));
    4383          26 : }
    4384             : 
    4385             : /* ----------
    4386             :  * pgstat_send_bgwriter() -
    4387             :  *
    4388             :  *      Send bgwriter statistics to the collector
    4389             :  * ----------
    4390             :  */
    4391             : void
    4392       11970 : pgstat_send_bgwriter(void)
    4393             : {
    4394             :     /* We assume this initializes to zeroes */
    4395             :     static const PgStat_MsgBgWriter all_zeroes;
    4396             : 
    4397             :     /*
    4398             :      * This function can be called even if nothing at all has happened. In
    4399             :      * this case, avoid sending a completely empty message to the stats
    4400             :      * collector.
    4401             :      */
    4402       11970 :     if (memcmp(&BgWriterStats, &all_zeroes, sizeof(PgStat_MsgBgWriter)) == 0)
    4403        5492 :         return;
    4404             : 
    4405             :     /*
    4406             :      * Prepare and send the message
    4407             :      */
    4408        6478 :     pgstat_setheader(&BgWriterStats.m_hdr, PGSTAT_MTYPE_BGWRITER);
    4409        6478 :     pgstat_send(&BgWriterStats, sizeof(BgWriterStats));
    4410             : 
    4411             :     /*
    4412             :      * Clear out the statistics buffer, so it can be re-used.
    4413             :      */
    4414        6478 :     MemSet(&BgWriterStats, 0, sizeof(BgWriterStats));
    4415             : }
    4416             : 
    4417             : 
    4418             : /* ----------
    4419             :  * PgstatCollectorMain() -
    4420             :  *
    4421             :  *  Start up the statistics collector process.  This is the body of the
    4422             :  *  postmaster child process.
    4423             :  *
    4424             :  *  The argc/argv parameters are valid only in EXEC_BACKEND case.
    4425             :  * ----------
    4426             :  */
    4427             : NON_EXEC_STATIC void
    4428         578 : PgstatCollectorMain(int argc, char *argv[])
    4429             : {
    4430             :     int         len;
    4431             :     PgStat_Msg  msg;
    4432             :     int         wr;
    4433             : 
    4434             :     /*
    4435             :      * Ignore all signals usually bound to some action in the postmaster,
    4436             :      * except SIGHUP and SIGQUIT.  Note we don't need a SIGUSR1 handler to
    4437             :      * support latch operations, because we only use a local latch.
    4438             :      */
    4439         578 :     pqsignal(SIGHUP, pgstat_sighup_handler);
    4440         578 :     pqsignal(SIGINT, SIG_IGN);
    4441         578 :     pqsignal(SIGTERM, SIG_IGN);
    4442         578 :     pqsignal(SIGQUIT, pgstat_exit);
    4443         578 :     pqsignal(SIGALRM, SIG_IGN);
    4444         578 :     pqsignal(SIGPIPE, SIG_IGN);
    4445         578 :     pqsignal(SIGUSR1, SIG_IGN);
    4446         578 :     pqsignal(SIGUSR2, SIG_IGN);
    4447             :     /* Reset some signals that are accepted by postmaster but not here */
    4448         578 :     pqsignal(SIGCHLD, SIG_DFL);
    4449         578 :     PG_SETMASK(&UnBlockSig);
    4450             : 
    4451             :     /*
    4452             :      * Identify myself via ps
    4453             :      */
    4454         578 :     init_ps_display("stats collector", "", "", "");
    4455             : 
    4456             :     /*
    4457             :      * Read in existing stats files or initialize the stats to zero.
    4458             :      */
    4459         578 :     pgStatRunningInCollector = true;
    4460         578 :     pgStatDBHash = pgstat_read_statsfiles(InvalidOid, true, true);
    4461             : 
    4462             :     /*
    4463             :      * Loop to process messages until we get SIGQUIT or detect ungraceful
    4464             :      * death of our parent postmaster.
    4465             :      *
    4466             :      * For performance reasons, we don't want to do ResetLatch/WaitLatch after
    4467             :      * every message; instead, do that only after a recv() fails to obtain a
    4468             :      * message.  (This effectively means that if backends are sending us stuff
    4469             :      * like mad, we won't notice postmaster death until things slack off a
    4470             :      * bit; which seems fine.)  To do that, we have an inner loop that
    4471             :      * iterates as long as recv() succeeds.  We do recognize got_SIGHUP inside
    4472             :      * the inner loop, which means that such interrupts will get serviced but
    4473             :      * the latch won't get cleared until next time there is a break in the
    4474             :      * action.
    4475             :      */
    4476             :     for (;;)
    4477             :     {
    4478             :         /* Clear any already-pending wakeups */
    4479      136654 :         ResetLatch(MyLatch);
    4480             : 
    4481             :         /*
    4482             :          * Quit if we get SIGQUIT from the postmaster.
    4483             :          */
    4484       68616 :         if (need_exit)
    4485         574 :             break;
    4486             : 
    4487             :         /*
    4488             :          * Inner loop iterates as long as we keep getting messages, or until
    4489             :          * need_exit becomes set.
    4490             :          */
    4491      238794 :         while (!need_exit)
    4492             :         {
    4493             :             /*
    4494             :              * Reload configuration if we got SIGHUP from the postmaster.
    4495             :              */
    4496      170752 :             if (got_SIGHUP)
    4497             :             {
    4498          48 :                 got_SIGHUP = false;
    4499          48 :                 ProcessConfigFile(PGC_SIGHUP);
    4500             :             }
    4501             : 
    4502             :             /*
    4503             :              * Write the stats file(s) if a new request has arrived that is
    4504             :              * not satisfied by existing file(s).
    4505             :              */
    4506      170752 :             if (pgstat_write_statsfile_needed())
    4507        1186 :                 pgstat_write_statsfiles(false, false);
    4508             : 
    4509             :             /*
    4510             :              * Try to receive and process a message.  This will not block,
    4511             :              * since the socket is set to non-blocking mode.
    4512             :              *
    4513             :              * XXX On Windows, we have to force pgwin32_recv to cooperate,
    4514             :              * despite the previous use of pg_set_noblock() on the socket.
    4515             :              * This is extremely broken and should be fixed someday.
    4516             :              */
    4517             : #ifdef WIN32
    4518             :             pgwin32_noblock = 1;
    4519             : #endif
    4520             : 
    4521      170752 :             len = recv(pgStatSock, (char *) &msg,
    4522             :                        sizeof(PgStat_Msg), 0);
    4523             : 
    4524             : #ifdef WIN32
    4525             :             pgwin32_noblock = 0;
    4526             : #endif
    4527             : 
    4528      170752 :             if (len < 0)
    4529             :             {
    4530       68042 :                 if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR)
    4531             :                     break;      /* out of inner loop */
    4532           0 :                 ereport(ERROR,
    4533             :                         (errcode_for_socket_access(),
    4534             :                          errmsg("could not read statistics message: %m")));
    4535             :             }
    4536             : 
    4537             :             /*
    4538             :              * We ignore messages that are smaller than our common header
    4539             :              */
    4540      102710 :             if (len < sizeof(PgStat_MsgHdr))
    4541           0 :                 continue;
    4542             : 
    4543             :             /*
    4544             :              * The received length must match the length in the header
    4545             :              */
    4546      102710 :             if (msg.msg_hdr.m_size != len)
    4547           0 :                 continue;
    4548             : 
    4549             :             /*
    4550             :              * O.K. - we accept this message.  Process it.
    4551             :              */
    4552      102710 :             switch (msg.msg_hdr.m_type)
    4553             :             {
    4554             :                 case PGSTAT_MTYPE_DUMMY:
    4555           0 :                     break;
    4556             : 
    4557             :                 case PGSTAT_MTYPE_INQUIRY:
    4558        1186 :                     pgstat_recv_inquiry(&msg.msg_inquiry, len);
    4559        1186 :                     break;
    4560             : 
    4561             :                 case PGSTAT_MTYPE_TABSTAT:
    4562       74976 :                     pgstat_recv_tabstat(&msg.msg_tabstat, len);
    4563       74976 :                     break;
    4564             : 
    4565             :                 case PGSTAT_MTYPE_TABPURGE:
    4566         898 :                     pgstat_recv_tabpurge(&msg.msg_tabpurge, len);
    4567         898 :                     break;
    4568             : 
    4569             :                 case PGSTAT_MTYPE_DROPDB:
    4570          16 :                     pgstat_recv_dropdb(&msg.msg_dropdb, len);
    4571          16 :                     break;
    4572             : 
    4573             :                 case PGSTAT_MTYPE_RESETCOUNTER:
    4574           0 :                     pgstat_recv_resetcounter(&msg.msg_resetcounter, len);
    4575           0 :                     break;
    4576             : 
    4577             :                 case PGSTAT_MTYPE_RESETSHAREDCOUNTER:
    4578           0 :                     pgstat_recv_resetsharedcounter(
    4579             :                                                    &msg.msg_resetsharedcounter,
    4580             :                                                    len);
    4581           0 :                     break;
    4582             : 
    4583             :                 case PGSTAT_MTYPE_RESETSINGLECOUNTER:
    4584           0 :                     pgstat_recv_resetsinglecounter(
    4585             :                                                    &msg.msg_resetsinglecounter,
    4586             :                                                    len);
    4587           0 :                     break;
    4588             : 
    4589             :                 case PGSTAT_MTYPE_AUTOVAC_START:
    4590          64 :                     pgstat_recv_autovac(&msg.msg_autovacuum_start, len);
    4591          64 :                     break;
    4592             : 
    4593             :                 case PGSTAT_MTYPE_VACUUM:
    4594        4568 :                     pgstat_recv_vacuum(&msg.msg_vacuum, len);
    4595        4568 :                     break;
    4596             : 
    4597             :                 case PGSTAT_MTYPE_ANALYZE:
    4598        9640 :                     pgstat_recv_analyze(&msg.msg_analyze, len);
    4599        9640 :                     break;
    4600             : 
    4601             :                 case PGSTAT_MTYPE_ARCHIVER:
    4602          26 :                     pgstat_recv_archiver(&msg.msg_archiver, len);
    4603          26 :                     break;
    4604             : 
    4605             :                 case PGSTAT_MTYPE_BGWRITER:
    4606        8140 :                     pgstat_recv_bgwriter(&msg.msg_bgwriter, len);
    4607        8140 :                     break;
    4608             : 
    4609             :                 case PGSTAT_MTYPE_FUNCSTAT:
    4610           0 :                     pgstat_recv_funcstat(&msg.msg_funcstat, len);
    4611           0 :                     break;
    4612             : 
    4613             :                 case PGSTAT_MTYPE_FUNCPURGE:
    4614           0 :                     pgstat_recv_funcpurge(&msg.msg_funcpurge, len);
    4615           0 :                     break;
    4616             : 
    4617             :                 case PGSTAT_MTYPE_RECOVERYCONFLICT:
    4618           0 :                     pgstat_recv_recoveryconflict(
    4619             :                                                  &msg.msg_recoveryconflict,
    4620             :                                                  len);
    4621           0 :                     break;
    4622             : 
    4623             :                 case PGSTAT_MTYPE_DEADLOCK:
    4624           4 :                     pgstat_recv_deadlock(&msg.msg_deadlock, len);
    4625           4 :                     break;
    4626             : 
    4627             :                 case PGSTAT_MTYPE_TEMPFILE:
    4628        3188 :                     pgstat_recv_tempfile(&msg.msg_tempfile, len);
    4629        3188 :                     break;
    4630             : 
    4631             :                 case PGSTAT_MTYPE_CHECKSUMFAILURE:
    4632           4 :                     pgstat_recv_checksum_failure(
    4633             :                                                  &msg.msg_checksumfailure,
    4634             :                                                  len);
    4635           4 :                     break;
    4636             : 
    4637             :                 default:
    4638           0 :                     break;
    4639             :             }
    4640             :         }                       /* end of inner message-processing loop */
    4641             : 
    4642             :         /* Sleep until there's something to do */
    4643             : #ifndef WIN32
    4644       68042 :         wr = WaitLatchOrSocket(MyLatch,
    4645             :                                WL_LATCH_SET | WL_POSTMASTER_DEATH | WL_SOCKET_READABLE,
    4646             :                                pgStatSock, -1L,
    4647             :                                WAIT_EVENT_PGSTAT_MAIN);
    4648             : #else
    4649             : 
    4650             :         /*
    4651             :          * Windows, at least in its Windows Server 2003 R2 incarnation,
    4652             :          * sometimes loses FD_READ events.  Waking up and retrying the recv()
    4653             :          * fixes that, so don't sleep indefinitely.  This is a crock of the
    4654             :          * first water, but until somebody wants to debug exactly what's
    4655             :          * happening there, this is the best we can do.  The two-second
    4656             :          * timeout matches our pre-9.2 behavior, and needs to be short enough
    4657             :          * to not provoke "using stale statistics" complaints from
    4658             :          * backend_read_statsfile.
    4659             :          */
    4660             :         wr = WaitLatchOrSocket(MyLatch,
    4661             :                                WL_LATCH_SET | WL_POSTMASTER_DEATH | WL_SOCKET_READABLE | WL_TIMEOUT,
    4662             :                                pgStatSock,
    4663             :                                2 * 1000L /* msec */ ,
    4664             :                                WAIT_EVENT_PGSTAT_MAIN);
    4665             : #endif
    4666             : 
    4667             :         /*
    4668             :          * Emergency bailout if postmaster has died.  This is to avoid the
    4669             :          * necessity for manual cleanup of all postmaster children.
    4670             :          */
    4671       68042 :         if (wr & WL_POSTMASTER_DEATH)
    4672           4 :             break;
    4673             :     }                           /* end of outer loop */
    4674             : 
    4675             :     /*
    4676             :      * Save the final stats to reuse at next startup.
    4677             :      */
    4678         578 :     pgstat_write_statsfiles(true, true);
    4679             : 
    4680         578 :     exit(0);
    4681             : }
    4682             : 
    4683             : 
    4684             : /* SIGQUIT signal handler for collector process */
    4685             : static void
    4686         582 : pgstat_exit(SIGNAL_ARGS)
    4687             : {
    4688         582 :     int         save_errno = errno;
    4689             : 
    4690         582 :     need_exit = true;
    4691         582 :     SetLatch(MyLatch);
    4692             : 
    4693         582 :     errno = save_errno;
    4694         582 : }
    4695             : 
    4696             : /* SIGHUP handler for collector process */
    4697             : static void
    4698          48 : pgstat_sighup_handler(SIGNAL_ARGS)
    4699             : {
    4700          48 :     int         save_errno = errno;
    4701             : 
    4702          48 :     got_SIGHUP = true;
    4703          48 :     SetLatch(MyLatch);
    4704             : 
    4705          48 :     errno = save_errno;
    4706          48 : }
    4707             : 
    4708             : /*
    4709             :  * Subroutine to clear stats in a database entry
    4710             :  *
    4711             :  * Tables and functions hashes are initialized to empty.
    4712             :  */
    4713             : static void
    4714        1072 : reset_dbentry_counters(PgStat_StatDBEntry *dbentry)
    4715             : {
    4716             :     HASHCTL     hash_ctl;
    4717             : 
    4718        1072 :     dbentry->n_xact_commit = 0;
    4719        1072 :     dbentry->n_xact_rollback = 0;
    4720        1072 :     dbentry->n_blocks_fetched = 0;
    4721        1072 :     dbentry->n_blocks_hit = 0;
    4722        1072 :     dbentry->n_tuples_returned = 0;
    4723        1072 :     dbentry->n_tuples_fetched = 0;
    4724        1072 :     dbentry->n_tuples_inserted = 0;
    4725        1072 :     dbentry->n_tuples_updated = 0;
    4726        1072 :     dbentry->n_tuples_deleted = 0;
    4727        1072 :     dbentry->last_autovac_time = 0;
    4728        1072 :     dbentry->n_conflict_tablespace = 0;
    4729        1072 :     dbentry->n_conflict_lock = 0;
    4730        1072 :     dbentry->n_conflict_snapshot = 0;
    4731        1072 :     dbentry->n_conflict_bufferpin = 0;
    4732        1072 :     dbentry->n_conflict_startup_deadlock = 0;
    4733        1072 :     dbentry->n_temp_files = 0;
    4734        1072 :     dbentry->n_temp_bytes = 0;
    4735        1072 :     dbentry->n_deadlocks = 0;
    4736        1072 :     dbentry->n_checksum_failures = 0;
    4737        1072 :     dbentry->last_checksum_failure = 0;
    4738        1072 :     dbentry->n_block_read_time = 0;
    4739        1072 :     dbentry->n_block_write_time = 0;
    4740             : 
    4741        1072 :     dbentry->stat_reset_timestamp = GetCurrentTimestamp();
    4742        1072 :     dbentry->stats_timestamp = 0;
    4743             : 
    4744        1072 :     memset(&hash_ctl, 0, sizeof(hash_ctl));
    4745        1072 :     hash_ctl.keysize = sizeof(Oid);
    4746        1072 :     hash_ctl.entrysize = sizeof(PgStat_StatTabEntry);
    4747        1072 :     dbentry->tables = hash_create("Per-database table",
    4748             :                                   PGSTAT_TAB_HASH_SIZE,
    4749             :                                   &hash_ctl,
    4750             :                                   HASH_ELEM | HASH_BLOBS);
    4751             : 
    4752        1072 :     hash_ctl.keysize = sizeof(Oid);
    4753        1072 :     hash_ctl.entrysize = sizeof(PgStat_StatFuncEntry);
    4754        1072 :     dbentry->functions = hash_create("Per-database function",
    4755             :                                      PGSTAT_FUNCTION_HASH_SIZE,
    4756             :                                      &hash_ctl,
    4757             :                                      HASH_ELEM | HASH_BLOBS);
    4758        1072 : }
    4759             : 
    4760             : /*
    4761             :  * Lookup the hash table entry for the specified database. If no hash
    4762             :  * table entry exists, initialize it, if the create parameter is true.
    4763             :  * Else, return NULL.
    4764             :  */
    4765             : static PgStat_StatDBEntry *
    4766       94544 : pgstat_get_db_entry(Oid databaseid, bool create)
    4767             : {
    4768             :     PgStat_StatDBEntry *result;
    4769             :     bool        found;
    4770       94544 :     HASHACTION  action = (create ? HASH_ENTER : HASH_FIND);
    4771             : 
    4772             :     /* Lookup or create the hash table entry for this database */
    4773       94544 :     result = (PgStat_StatDBEntry *) hash_search(pgStatDBHash,
    4774             :                                                 &databaseid,
    4775             :                                                 action, &found);
    4776             : 
    4777       94544 :     if (!create && !found)
    4778         364 :         return NULL;
    4779             : 
    4780             :     /*
    4781             :      * If not found, initialize the new one.  This creates empty hash tables
    4782             :      * for tables and functions, too.
    4783             :      */
    4784       94180 :     if (!found)
    4785        1072 :         reset_dbentry_counters(result);
    4786             : 
    4787       94180 :     return result;
    4788             : }
    4789             : 
    4790             : 
    4791             : /*
    4792             :  * Lookup the hash table entry for the specified table. If no hash
    4793             :  * table entry exists, initialize it, if the create parameter is true.
    4794             :  * Else, return NULL.
    4795             :  */
    4796             : static PgStat_StatTabEntry *
    4797       14208 : pgstat_get_tab_entry(PgStat_StatDBEntry *dbentry, Oid tableoid, bool create)
    4798             : {
    4799             :     PgStat_StatTabEntry *result;
    4800             :     bool        found;
    4801       14208 :     HASHACTION  action = (create ? HASH_ENTER : HASH_FIND);
    4802             : 
    4803             :     /* Lookup or create the hash table entry for this table */
    4804       14208 :     result = (PgStat_StatTabEntry *) hash_search(dbentry->tables,
    4805             :                                                  &tableoid,
    4806             :                                                  action, &found);
    4807             : 
    4808       14208 :     if (!create && !found)
    4809           0 :         return NULL;
    4810             : 
    4811             :     /* If not found, initialize the new one. */
    4812       14208 :     if (!found)
    4813             :     {
    4814        4004 :         result->numscans = 0;
    4815        4004 :         result->tuples_returned = 0;
    4816        4004 :         result->tuples_fetched = 0;
    4817        4004 :         result->tuples_inserted = 0;
    4818        4004 :         result->tuples_updated = 0;
    4819        4004 :         result->tuples_deleted = 0;
    4820        4004 :         result->tuples_hot_updated = 0;
    4821        4004 :         result->n_live_tuples = 0;
    4822        4004 :         result->n_dead_tuples = 0;
    4823        4004 :         result->changes_since_analyze = 0;
    4824        4004 :         result->blocks_fetched = 0;
    4825        4004 :         result->blocks_hit = 0;
    4826        4004 :         result->vacuum_timestamp = 0;
    4827        4004 :         result->vacuum_count = 0;
    4828        4004 :         result->autovac_vacuum_timestamp = 0;
    4829        4004 :         result->autovac_vacuum_count = 0;
    4830        4004 :         result->analyze_timestamp = 0;
    4831        4004 :         result->analyze_count = 0;
    4832        4004 :         result->autovac_analyze_timestamp = 0;
    4833        4004 :         result->autovac_analyze_count = 0;
    4834             :     }
    4835             : 
    4836       14208 :     return result;
    4837             : }
    4838             : 
    4839             : 
    4840             : /* ----------
    4841             :  * pgstat_write_statsfiles() -
    4842             :  *      Write the global statistics file, as well as requested DB files.
    4843             :  *
    4844             :  *  'permanent' specifies writing to the permanent files not temporary ones.
    4845             :  *  When true (happens only when the collector is shutting down), also remove
    4846             :  *  the temporary files so that backends starting up under a new postmaster
    4847             :  *  can't read old data before the new collector is ready.
    4848             :  *
    4849             :  *  When 'allDbs' is false, only the requested databases (listed in
    4850             :  *  pending_write_requests) will be written; otherwise, all databases
    4851             :  *  will be written.
    4852             :  * ----------
    4853             :  */
    4854             : static void
    4855        1764 : pgstat_write_statsfiles(bool permanent, bool allDbs)
    4856             : {
    4857             :     HASH_SEQ_STATUS hstat;
    4858             :     PgStat_StatDBEntry *dbentry;
    4859             :     FILE       *fpout;
    4860             :     int32       format_id;
    4861        1764 :     const char *tmpfile = permanent ? PGSTAT_STAT_PERMANENT_TMPFILE : pgstat_stat_tmpname;
    4862        1764 :     const char *statfile = permanent ? PGSTAT_STAT_PERMANENT_FILENAME : pgstat_stat_filename;
    4863             :     int         rc;
    4864             : 
    4865        1764 :     elog(DEBUG2, "writing stats file \"%s\"", statfile);
    4866             : 
    4867             :     /*
    4868             :      * Open the statistics temp file to write out the current values.
    4869             :      */
    4870        1764 :     fpout = AllocateFile(tmpfile, PG_BINARY_W);
    4871        1764 :     if (fpout == NULL)
    4872             :     {
    4873           0 :         ereport(LOG,
    4874             :                 (errcode_for_file_access(),
    4875             :                  errmsg("could not open temporary statistics file \"%s\": %m",
    4876             :                         tmpfile)));
    4877           0 :         return;
    4878             :     }
    4879             : 
    4880             :     /*
    4881             :      * Set the timestamp of the stats file.
    4882             :      */
    4883        1764 :     globalStats.stats_timestamp = GetCurrentTimestamp();
    4884             : 
    4885             :     /*
    4886             :      * Write the file header --- currently just a format ID.
    4887             :      */
    4888        1764 :     format_id = PGSTAT_FILE_FORMAT_ID;
    4889        1764 :     rc = fwrite(&format_id, sizeof(format_id), 1, fpout);
    4890             :     (void) rc;                  /* we'll check for error with ferror */
    4891             : 
    4892             :     /*
    4893             :      * Write global stats struct
    4894             :      */
    4895        1764 :     rc = fwrite(&globalStats, sizeof(globalStats), 1, fpout);
    4896             :     (void) rc;                  /* we'll check for error with ferror */
    4897             : 
    4898             :     /*
    4899             :      * Write archiver stats struct
    4900             :      */
    4901        1764 :     rc = fwrite(&archiverStats, sizeof(archiverStats), 1, fpout);
    4902             :     (void) rc;                  /* we'll check for error with ferror */
    4903             : 
    4904             :     /*
    4905             :      * Walk through the database table.
    4906             :      */
    4907        1764 :     hash_seq_init(&hstat, pgStatDBHash);
    4908        7230 :     while ((dbentry = (PgStat_StatDBEntry *) hash_seq_search(&hstat)) != NULL)
    4909             :     {
    4910             :         /*
    4911             :          * Write out the table and function stats for this DB into the
    4912             :          * appropriate per-DB stat file, if required.
    4913             :          */
    4914        3702 :         if (allDbs || pgstat_db_requested(dbentry->databaseid))
    4915             :         {
    4916             :             /* Make DB's timestamp consistent with the global stats */
    4917        2782 :             dbentry->stats_timestamp = globalStats.stats_timestamp;
    4918             : 
    4919        2782 :             pgstat_write_db_statsfile(dbentry, permanent);
    4920             :         }
    4921             : 
    4922             :         /*
    4923             :          * Write out the DB entry. We don't write the tables or functions
    4924             :          * pointers, since they're of no use to any other process.
    4925             :          */
    4926        3702 :         fputc('D', fpout);
    4927        3702 :         rc = fwrite(dbentry, offsetof(PgStat_StatDBEntry, tables), 1, fpout);
    4928             :         (void) rc;              /* we'll check for error with ferror */
    4929             :     }
    4930             : 
    4931             :     /*
    4932             :      * No more output to be done. Close the temp file and replace the old
    4933             :      * pgstat.stat with it.  The ferror() check replaces testing for error
    4934             :      * after each individual fputc or fwrite above.
    4935             :      */
    4936        1764 :     fputc('E', fpout);
    4937             : 
    4938        1764 :     if (ferror(fpout))
    4939             :     {
    4940           0 :         ereport(LOG,
    4941             :                 (errcode_for_file_access(),
    4942             :                  errmsg("could not write temporary statistics file \"%s\": %m",
    4943             :                         tmpfile)));
    4944           0 :         FreeFile(fpout);
    4945           0 :         unlink(tmpfile);
    4946             :     }
    4947        1764 :     else if (FreeFile(fpout) < 0)
    4948             :     {
    4949           0 :         ereport(LOG,
    4950             :                 (errcode_for_file_access(),
    4951             :                  errmsg("could not close temporary statistics file \"%s\": %m",
    4952             :                         tmpfile)));
    4953           0 :         unlink(tmpfile);
    4954             :     }
    4955        1764 :     else if (rename(tmpfile, statfile) < 0)
    4956             :     {
    4957           0 :         ereport(LOG,
    4958             :                 (errcode_for_file_access(),
    4959             :                  errmsg("could not rename temporary statistics file \"%s\" to \"%s\": %m",
    4960             :                         tmpfile, statfile)));
    4961           0 :         unlink(tmpfile);
    4962             :     }
    4963             : 
    4964        1764 :     if (permanent)
    4965         578 :         unlink(pgstat_stat_filename);
    4966             : 
    4967             :     /*
    4968             :      * Now throw away the list of requests.  Note that requests sent after we
    4969             :      * started the write are still waiting on the network socket.
    4970             :      */
    4971        1764 :     list_free(pending_write_requests);
    4972        1764 :     pending_write_requests = NIL;
    4973             : }
    4974             : 
    4975             : /*
    4976             :  * return the filename for a DB stat file; filename is the output buffer,
    4977             :  * of length len.
    4978             :  */
    4979             : static void
    4980       12104 : get_dbstat_filename(bool permanent, bool tempname, Oid databaseid,
    4981             :                     char *filename, int len)
    4982             : {
    4983             :     int         printed;
    4984             : 
    4985             :     /* NB -- pgstat_reset_remove_files knows about the pattern this uses */
    4986       12104 :     printed = snprintf(filename, len, "%s/db_%u.%s",
    4987             :                        permanent ? PGSTAT_STAT_PERMANENT_DIRECTORY :
    4988             :                        pgstat_stat_directory,
    4989             :                        databaseid,
    4990             :                        tempname ? "tmp" : "stat");
    4991       12104 :     if (printed >= len)
    4992           0 :         elog(ERROR, "overlength pgstat path");
    4993       12104 : }
    4994             : 
    4995             : /* ----------
    4996             :  * pgstat_write_db_statsfile() -
    4997             :  *      Write the stat file for a single database.
    4998             :  *
    4999             :  *  If writing to the permanent file (happens when the collector is
    5000             :  *  shutting down only), remove the temporary file so that backends
    5001             :  *  starting up under a new postmaster can't read the old data before
    5002             :  *  the new collector is ready.
    5003             :  * ----------
    5004             :  */
    5005             : static void
    5006        2782 : pgstat_write_db_statsfile(PgStat_StatDBEntry *dbentry, bool permanent)
    5007             : {
    5008             :     HASH_SEQ_STATUS tstat;
    5009             :     HASH_SEQ_STATUS fstat;
    5010             :     PgStat_StatTabEntry *tabentry;
    5011             :     PgStat_StatFuncEntry *funcentry;
    5012             :     FILE       *fpout;
    5013             :     int32       format_id;
    5014        2782 :     Oid         dbid = dbentry->databaseid;
    5015             :     int         rc;
    5016             :     char        tmpfile[MAXPGPATH];
    5017             :     char        statfile[MAXPGPATH];
    5018             : 
    5019        2782 :     get_dbstat_filename(permanent, true, dbid, tmpfile, MAXPGPATH);
    5020        2782 :     get_dbstat_filename(permanent, false, dbid, statfile, MAXPGPATH);
    5021             : 
    5022        2782 :     elog(DEBUG2, "writing stats file \"%s\"", statfile);
    5023             : 
    5024             :     /*
    5025             :      * Open the statistics temp file to write out the current values.
    5026             :      */
    5027        2782 :     fpout = AllocateFile(tmpfile, PG_BINARY_W);
    5028        2782 :     if (fpout == NULL)
    5029             :     {
    5030           0 :         ereport(LOG,
    5031             :                 (errcode_for_file_access(),
    5032             :                  errmsg("could not open temporary statistics file \"%s\": %m",
    5033             :                         tmpfile)));
    5034           0 :         return;
    5035             :     }
    5036             : 
    5037             :     /*
    5038             :      * Write the file header --- currently just a format ID.
    5039             :      */
    5040        2782 :     format_id = PGSTAT_FILE_FORMAT_ID;
    5041        2782 :     rc = fwrite(&format_id, sizeof(format_id), 1, fpout);
    5042             :     (void) rc;                  /* we'll check for error with ferror */
    5043             : 
    5044             :     /*
    5045             :      * Walk through the database's access stats per table.
    5046             :      */
    5047        2782 :     hash_seq_init(&tstat, dbentry->tables);
    5048      444634 :     while ((tabentry = (PgStat_StatTabEntry *) hash_seq_search(&tstat)) != NULL)
    5049             :     {
    5050      439070 :         fputc('T', fpout);
    5051      439070 :         rc = fwrite(tabentry, sizeof(PgStat_StatTabEntry), 1, fpout);
    5052             :         (void) rc;              /* we'll check for error with ferror */
    5053             :     }
    5054             : 
    5055             :     /*
    5056             :      * Walk through the database's function stats table.
    5057             :      */
    5058        2782 :     hash_seq_init(&fstat, dbentry->functions);
    5059        5564 :     while ((funcentry = (PgStat_StatFuncEntry *) hash_seq_search(&fstat)) != NULL)
    5060             :     {
    5061           0 :         fputc('F', fpout);
    5062           0 :         rc = fwrite(funcentry, sizeof(PgStat_StatFuncEntry), 1, fpout);
    5063             :         (void) rc;              /* we'll check for error with ferror */
    5064             :     }
    5065             : 
    5066             :     /*
    5067             :      * No more output to be done. Close the temp file and replace the old
    5068             :      * pgstat.stat with it.  The ferror() check replaces testing for error
    5069             :      * after each individual fputc or fwrite above.
    5070             :      */
    5071        2782 :     fputc('E', fpout);
    5072             : 
    5073        2782 :     if (ferror(fpout))
    5074             :     {
    5075           0 :         ereport(LOG,
    5076             :                 (errcode_for_file_access(),
    5077             :                  errmsg("could not write temporary statistics file \"%s\": %m",
    5078             :                         tmpfile)));
    5079           0 :         FreeFile(fpout);
    5080           0 :         unlink(tmpfile);
    5081             :     }
    5082        2782 :     else if (FreeFile(fpout) < 0)
    5083             :     {
    5084           0 :         ereport(LOG,
    5085             :                 (errcode_for_file_access(),
    5086             :                  errmsg("could not close temporary statistics file \"%s\": %m",
    5087             :                         tmpfile)));
    5088           0 :         unlink(tmpfile);
    5089             :     }
    5090        2782 :     else if (rename(tmpfile, statfile) < 0)
    5091             :     {
    5092           0 :         ereport(LOG,
    5093             :                 (errcode_for_file_access(),
    5094             :                  errmsg("could not rename temporary statistics file \"%s\" to \"%s\": %m",
    5095             :                         tmpfile, statfile)));
    5096           0 :         unlink(tmpfile);
    5097             :     }
    5098             : 
    5099        2782 :     if (permanent)
    5100             :     {
    5101        1316 :         get_dbstat_filename(false, false, dbid, statfile, MAXPGPATH);
    5102             : 
    5103        1316 :         elog(DEBUG2, "removing temporary stats file \"%s\"", statfile);
    5104        1316 :         unlink(statfile);
    5105             :     }
    5106             : }
    5107             : 
    5108             : /* ----------
    5109             :  * pgstat_read_statsfiles() -
    5110             :  *
    5111             :  *  Reads in some existing statistics collector files and returns the
    5112             :  *  databases hash table that is the top level of the data.
    5113             :  *
    5114             :  *  If 'onlydb' is not InvalidOid, it means we only want data for that DB
    5115             :  *  plus the shared catalogs ("DB 0").  We'll still populate the DB hash
    5116             :  *  table for all databases, but we don't bother even creating table/function
    5117             :  *  hash tables for other databases.
    5118             :  *
    5119             :  *  'permanent' specifies reading from the permanent files not temporary ones.
    5120             :  *  When true (happens only when the collector is starting up), remove the
    5121             :  *  files after reading; the in-memory status is now authoritative, and the
    5122             :  *  files would be out of date in case somebody else reads them.
    5123             :  *
    5124             :  *  If a 'deep' read is requested, table/function stats are read, otherwise
    5125             :  *  the table/function hash tables remain empty.
    5126             :  * ----------
    5127             :  */
    5128             : static HTAB *
    5129        4190 : pgstat_read_statsfiles(Oid onlydb, bool permanent, bool deep)
    5130             : {
    5131             :     PgStat_StatDBEntry *dbentry;
    5132             :     PgStat_StatDBEntry dbbuf;
    5133             :     HASHCTL     hash_ctl;
    5134             :     HTAB       *dbhash;
    5135             :     FILE       *fpin;
    5136             :     int32       format_id;
    5137             :     bool        found;
    5138        4190 :     const char *statfile = permanent ? PGSTAT_STAT_PERMANENT_FILENAME : pgstat_stat_filename;
    5139             : 
    5140             :     /*
    5141             :      * The tables will live in pgStatLocalContext.
    5142             :      */
    5143        4190 :     pgstat_setup_memcxt();
    5144             : 
    5145             :     /*
    5146             :      * Create the DB hashtable
    5147             :      */
    5148        4190 :     memset(&hash_ctl, 0, sizeof(hash_ctl));
    5149        4190 :     hash_ctl.keysize = sizeof(Oid);
    5150        4190 :     hash_ctl.entrysize = sizeof(PgStat_StatDBEntry);
    5151        4190 :     hash_ctl.hcxt = pgStatLocalContext;
    5152        4190 :     dbhash = hash_create("Databases hash", PGSTAT_DB_HASH_SIZE, &hash_ctl,
    5153             :                          HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
    5154             : 
    5155             :     /*
    5156             :      * Clear out global and archiver statistics so they start from zero in
    5157             :      * case we can't load an existing statsfile.
    5158             :      */
    5159        4190 :     memset(&globalStats, 0, sizeof(globalStats));
    5160        4190 :     memset(&archiverStats, 0, sizeof(archiverStats));
    5161             : 
    5162             :     /*
    5163             :      * Set the current timestamp (will be kept only in case we can't load an
    5164             :      * existing statsfile).
    5165             :      */
    5166        4190 :     globalStats.stat_reset_timestamp = GetCurrentTimestamp();
    5167        4190 :     archiverStats.stat_reset_timestamp = globalStats.stat_reset_timestamp;
    5168             : 
    5169             :     /*
    5170             :      * Try to open the stats file. If it doesn't exist, the backends simply
    5171             :      * return zero for anything and the collector simply starts from scratch
    5172             :      * with empty counters.
    5173             :      *
    5174             :      * ENOENT is a possibility if the stats collector is not running or has
    5175             :      * not yet written the stats file the first time.  Any other failure
    5176             :      * condition is suspicious.
    5177             :      */
    5178        4190 :     if ((fpin = AllocateFile(statfile, PG_BINARY_R)) == NULL)
    5179             :     {
    5180         458 :         if (errno != ENOENT)
    5181           0 :             ereport(pgStatRunningInCollector ? LOG : WARNING,
    5182             :                     (errcode_for_file_access(),
    5183             :                      errmsg("could not open statistics file \"%s\": %m",
    5184             :                             statfile)));
    5185         458 :         return dbhash;
    5186             :     }
    5187             : 
    5188             :     /*
    5189             :      * Verify it's of the expected format.
    5190             :      */
    5191        7464 :     if (fread(&format_id, 1, sizeof(format_id), fpin) != sizeof(format_id) ||
    5192        3732 :         format_id != PGSTAT_FILE_FORMAT_ID)
    5193             :     {
    5194           0 :         ereport(pgStatRunningInCollector ? LOG : WARNING,
    5195             :                 (errmsg("corrupted statistics file \"%s\"", statfile)));
    5196           0 :         goto done;
    5197             :     }
    5198             : 
    5199             :     /*
    5200             :      * Read global stats struct
    5201             :      */
    5202        3732 :     if (fread(&globalStats, 1, sizeof(globalStats), fpin) != sizeof(globalStats))
    5203             :     {
    5204           0 :         ereport(pgStatRunningInCollector ? LOG : WARNING,
    5205             :                 (errmsg("corrupted statistics file \"%s\"", statfile)));
    5206           0 :         memset(&globalStats, 0, sizeof(globalStats));
    5207           0 :         goto done;
    5208             :     }
    5209             : 
    5210             :     /*
    5211             :      * In the collector, disregard the timestamp we read from the permanent
    5212             :      * stats file; we should be willing to write a temp stats file immediately
    5213             :      * upon the first request from any backend.  This only matters if the old
    5214             :      * file's timestamp is less than PGSTAT_STAT_INTERVAL ago, but that's not
    5215             :      * an unusual scenario.
    5216             :      */
    5217        3732 :     if (pgStatRunningInCollector)
    5218         120 :         globalStats.stats_timestamp = 0;
    5219             : 
    5220             :     /*
    5221             :      * Read archiver stats struct
    5222             :      */
    5223        3732 :     if (fread(&archiverStats, 1, sizeof(archiverStats), fpin) != sizeof(archiverStats))
    5224             :     {
    5225           0 :         ereport(pgStatRunningInCollector ? LOG : WARNING,
    5226             :                 (errmsg("corrupted statistics file \"%s\"", statfile)));
    5227           0 :         memset(&archiverStats, 0, sizeof(archiverStats));
    5228           0 :         goto done;
    5229             :     }
    5230             : 
    5231             :     /*
    5232             :      * We found an existing collector stats file. Read it and put all the
    5233             :      * hashtable entries into place.
    5234             :      */
    5235             :     for (;;)
    5236             :     {
    5237       18572 :         switch (fgetc(fpin))
    5238             :         {
    5239             :                 /*
    5240             :                  * 'D'  A PgStat_StatDBEntry struct describing a database
    5241             :                  * follows.
    5242             :                  */
    5243             :             case 'D':
    5244        7420 :                 if (fread(&dbbuf, 1, offsetof(PgStat_StatDBEntry, tables),
    5245             :                           fpin) != offsetof(PgStat_StatDBEntry, tables))
    5246             :                 {
    5247           0 :                     ereport(pgStatRunningInCollector ? LOG : WARNING,
    5248             :                             (errmsg("corrupted statistics file \"%s\"",
    5249             :                                     statfile)));
    5250           0 :                     goto done;
    5251             :                 }
    5252             : 
    5253             :                 /*
    5254             :                  * Add to the DB hash
    5255             :                  */
    5256        7420 :                 dbentry = (PgStat_StatDBEntry *) hash_search(dbhash,
    5257             :                                                              (void *) &dbbuf.databaseid,
    5258             :                                                              HASH_ENTER,
    5259             :                                                              &found);
    5260        7420 :                 if (found)
    5261             :                 {
    5262           0 :                     ereport(pgStatRunningInCollector ? LOG : WARNING,
    5263             :                             (errmsg("corrupted statistics file \"%s\"",
    5264             :                                     statfile)));
    5265           0 :                     goto done;
    5266             :                 }
    5267             : 
    5268        7420 :                 memcpy(dbentry, &dbbuf, sizeof(PgStat_StatDBEntry));
    5269        7420 :                 dbentry->tables = NULL;
    5270        7420 :                 dbentry->functions = NULL;
    5271             : 
    5272             :                 /*
    5273             :                  * In the collector, disregard the timestamp we read from the
    5274             :                  * permanent stats file; we should be willing to write a temp
    5275             :                  * stats file immediately upon the first request from any
    5276             :                  * backend.
    5277             :                  */
    5278        7420 :                 if (pgStatRunningInCollector)
    5279         254 :                     dbentry->stats_timestamp = 0;
    5280             : 
    5281             :                 /*
    5282             :                  * Don't create tables/functions hashtables for uninteresting
    5283             :                  * databases.
    5284             :                  */
    5285        7420 :                 if (onlydb != InvalidOid)
    5286             :                 {
    5287       10916 :                     if (dbbuf.databaseid != onlydb &&
    5288        4218 :                         dbbuf.databaseid != InvalidOid)
    5289        1738 :                         break;
    5290             :                 }
    5291             : 
    5292        5682 :                 memset(&hash_ctl, 0, sizeof(hash_ctl));
    5293        5682 :                 hash_ctl.keysize = sizeof(Oid);
    5294        5682 :                 hash_ctl.entrysize = sizeof(PgStat_StatTabEntry);
    5295        5682 :                 hash_ctl.hcxt = pgStatLocalContext;
    5296        5682 :                 dbentry->tables = hash_create("Per-database table",
    5297             :                                               PGSTAT_TAB_HASH_SIZE,
    5298             :                                               &hash_ctl,
    5299             :                                               HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
    5300             : 
    5301        5682 :                 hash_ctl.keysize = sizeof(Oid);
    5302        5682 :                 hash_ctl.entrysize = sizeof(PgStat_StatFuncEntry);
    5303        5682 :                 hash_ctl.hcxt = pgStatLocalContext;
    5304        5682 :                 dbentry->functions = hash_create("Per-database function",
    5305             :                                                  PGSTAT_FUNCTION_HASH_SIZE,
    5306             :                                                  &hash_ctl,
    5307             :                                                  HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
    5308             : 
    5309             :                 /*
    5310             :                  * If requested, read the data from the database-specific
    5311             :                  * file.  Otherwise we just leave the hashtables empty.
    5312             :                  */
    5313        5682 :                 if (deep)
    5314        5214 :                     pgstat_read_db_statsfile(dbentry->databaseid,
    5315             :                                              dbentry->tables,
    5316             :                                              dbentry->functions,
    5317             :                                              permanent);
    5318             : 
    5319        5682 :                 break;
    5320             : 
    5321             :             case 'E':
    5322        3732 :                 goto done;
    5323             : 
    5324             :             default:
    5325           0 :                 ereport(pgStatRunningInCollector ? LOG : WARNING,
    5326             :                         (errmsg("corrupted statistics file \"%s\"",
    5327             :                                 statfile)));
    5328           0 :                 goto done;
    5329             :         }
    5330             :     }
    5331             : 
    5332             : done:
    5333        3732 :     FreeFile(fpin);
    5334             : 
    5335             :     /* If requested to read the permanent file, also get rid of it. */
    5336        3732 :     if (permanent)
    5337             :     {
    5338         120 :         elog(DEBUG2, "removing permanent stats file \"%s\"", statfile);
    5339         120 :         unlink(statfile);
    5340             :     }
    5341             : 
    5342        3732 :     return dbhash;
    5343             : }
    5344             : 
    5345             : 
    5346             : /* ----------
    5347             :  * pgstat_read_db_statsfile() -
    5348             :  *
    5349             :  *  Reads in the existing statistics collector file for the given database,
    5350             :  *  filling the passed-in tables and functions hash tables.
    5351             :  *
    5352             :  *  As in pgstat_read_statsfiles, if the permanent file is requested, it is
    5353             :  *  removed after reading.
    5354             :  *
    5355             :  *  Note: this code has the ability to skip storing per-table or per-function
    5356             :  *  data, if NULL is passed for the corresponding hashtable.  That's not used
    5357             :  *  at the moment though.
    5358             :  * ----------
    5359             :  */
    5360             : static void
    5361        5214 : pgstat_read_db_statsfile(Oid databaseid, HTAB *tabhash, HTAB *funchash,
    5362             :                          bool permanent)
    5363             : {
    5364             :     PgStat_StatTabEntry *tabentry;
    5365             :     PgStat_StatTabEntry tabbuf;
    5366             :     PgStat_StatFuncEntry funcbuf;
    5367             :     PgStat_StatFuncEntry *funcentry;
    5368             :     FILE       *fpin;
    5369             :     int32       format_id;
    5370             :     bool        found;
    5371             :     char        statfile[MAXPGPATH];
    5372             : 
    5373        5214 :     get_dbstat_filename(permanent, false, databaseid, statfile, MAXPGPATH);
    5374             : 
    5375             :     /*
    5376             :      * Try to open the stats file. If it doesn't exist, the backends simply
    5377             :      * return zero for anything and the collector simply starts from scratch
    5378             :      * with empty counters.
    5379             :      *
    5380             :      * ENOENT is a possibility if the stats collector is not running or has
    5381             :      * not yet written the stats file the first time.  Any other failure
    5382             :      * condition is suspicious.
    5383             :      */
    5384        5214 :     if ((fpin = AllocateFile(statfile, PG_BINARY_R)) == NULL)
    5385             :     {
    5386           0 :         if (errno != ENOENT)
    5387           0 :             ereport(pgStatRunningInCollector ? LOG : WARNING,
    5388             :                     (errcode_for_file_access(),
    5389             :                      errmsg("could not open statistics file \"%s\": %m",
    5390             :                             statfile)));
    5391           0 :         return;
    5392             :     }
    5393             : 
    5394             :     /*
    5395             :      * Verify it's of the expected format.
    5396             :      */
    5397       10428 :     if (fread(&format_id, 1, sizeof(format_id), fpin) != sizeof(format_id) ||
    5398        5214 :         format_id != PGSTAT_FILE_FORMAT_ID)
    5399             :     {
    5400           0 :         ereport(pgStatRunningInCollector ? LOG : WARNING,
    5401             :                 (errmsg("corrupted statistics file \"%s\"", statfile)));
    5402           0 :         goto done;
    5403             :     }
    5404             : 
    5405             :     /*
    5406             :      * We found an existing collector stats file. Read it and put all the
    5407             :      * hashtable entries into place.
    5408             :      */
    5409             :     for (;;)
    5410             :     {
    5411     1879282 :         switch (fgetc(fpin))
    5412             :         {
    5413             :                 /*
    5414             :                  * 'T'  A PgStat_StatTabEntry follows.
    5415             :                  */
    5416             :             case 'T':
    5417      937034 :                 if (fread(&tabbuf, 1, sizeof(PgStat_StatTabEntry),
    5418             :                           fpin) != sizeof(PgStat_StatTabEntry))
    5419             :                 {
    5420           0 :                     ereport(pgStatRunningInCollector ? LOG : WARNING,
    5421             :                             (errmsg("corrupted statistics file \"%s\"",
    5422             :                                     statfile)));
    5423           0 :                     goto done;
    5424             :                 }
    5425             : 
    5426             :                 /*
    5427             :                  * Skip if table data not wanted.
    5428             :                  */
    5429      937034 :                 if (tabhash == NULL)
    5430           0 :                     break;
    5431             : 
    5432      937034 :                 tabentry = (PgStat_StatTabEntry *) hash_search(tabhash,
    5433             :                                                                (void *) &tabbuf.tableid,
    5434             :                                                                HASH_ENTER, &found);
    5435             : 
    5436      937034 :                 if (found)
    5437             :                 {
    5438           0 :                     ereport(pgStatRunningInCollector ? LOG : WARNING,
    5439             :                             (errmsg("corrupted statistics file \"%s\"",
    5440             :                                     statfile)));
    5441           0 :                     goto done;
    5442             :                 }
    5443             : 
    5444      937034 :                 memcpy(tabentry, &tabbuf, sizeof(tabbuf));
    5445      937034 :                 break;
    5446             : 
    5447             :                 /*
    5448             :                  * 'F'  A PgStat_StatFuncEntry follows.
    5449             :                  */
    5450             :             case 'F':
    5451           0 :                 if (fread(&funcbuf, 1, sizeof(PgStat_StatFuncEntry),
    5452             :                           fpin) != sizeof(PgStat_StatFuncEntry))
    5453             :                 {
    5454           0 :                     ereport(pgStatRunningInCollector ? LOG : WARNING,
    5455             :                             (errmsg("corrupted statistics file \"%s\"",
    5456             :                                     statfile)));
    5457           0 :                     goto done;
    5458             :                 }
    5459             : 
    5460             :                 /*
    5461             :                  * Skip if function data not wanted.
    5462             :                  */
    5463           0 :                 if (funchash == NULL)
    5464           0 :                     break;
    5465             : 
    5466           0 :                 funcentry = (PgStat_StatFuncEntry *) hash_search(funchash,
    5467             :                                                                  (void *) &funcbuf.functionid,
    5468             :                                                                  HASH_ENTER, &found);
    5469             : 
    5470           0 :                 if (found)
    5471             :                 {
    5472           0 :                     ereport(pgStatRunningInCollector ? LOG : WARNING,
    5473             :                             (errmsg("corrupted statistics file \"%s\"",
    5474             :                                     statfile)));
    5475           0 :                     goto done;
    5476             :                 }
    5477             : 
    5478           0 :                 memcpy(funcentry, &funcbuf, sizeof(funcbuf));
    5479           0 :                 break;
    5480             : 
    5481             :                 /*
    5482             :                  * 'E'  The EOF marker of a complete stats file.
    5483             :                  */
    5484             :             case 'E':
    5485        5214 :                 goto done;
    5486             : 
    5487             :             default:
    5488           0 :                 ereport(pgStatRunningInCollector ? LOG : WARNING,
    5489             :                         (errmsg("corrupted statistics file \"%s\"",
    5490             :                                 statfile)));
    5491           0 :                 goto done;
    5492             :         }
    5493             :     }
    5494             : 
    5495             : done:
    5496        5214 :     FreeFile(fpin);
    5497             : 
    5498        5214 :     if (permanent)
    5499             :     {
    5500         254 :         elog(DEBUG2, "removing permanent stats file \"%s\"", statfile);
    5501         254 :         unlink(statfile);
    5502             :     }
    5503             : }
    5504             : 
    5505             : /* ----------
    5506             :  * pgstat_read_db_statsfile_timestamp() -
    5507             :  *
    5508             :  *  Attempt to determine the timestamp of the last db statfile write.
    5509             :  *  Returns true if successful; the timestamp is stored in *ts.
    5510             :  *
    5511             :  *  This needs to be careful about handling databases for which no stats file
    5512             :  *  exists, such as databases without a stat entry or those not yet written:
    5513             :  *
    5514             :  *  - if there's a database entry in the global file, return the corresponding
    5515             :  *  stats_timestamp value.
    5516             :  *
    5517             :  *  - if there's no db stat entry (e.g. for a new or inactive database),
    5518             :  *  there's no stats_timestamp value, but also nothing to write so we return
    5519             :  *  the timestamp of the global statfile.
    5520             :  * ----------
    5521             :  */
    5522             : static bool
    5523        5886 : pgstat_read_db_statsfile_timestamp(Oid databaseid, bool permanent,
    5524             :                                    TimestampTz *ts)
    5525             : {
    5526             :     PgStat_StatDBEntry dbentry;
    5527             :     PgStat_GlobalStats myGlobalStats;
    5528             :     PgStat_ArchiverStats myArchiverStats;
    5529             :     FILE       *fpin;
    5530             :     int32       format_id;
    5531        5886 :     const char *statfile = permanent ? PGSTAT_STAT_PERMANENT_FILENAME : pgstat_stat_filename;
    5532             : 
    5533             :     /*
    5534             :      * Try to open the stats file.  As above, anything but ENOENT is worthy of
    5535             :      * complaining about.
    5536             :      */
    5537        5886 :     if ((fpin = AllocateFile(statfile, PG_BINARY_R)) == NULL)
    5538             :     {
    5539        1592 :         if (errno != ENOENT)
    5540           0 :             ereport(pgStatRunningInCollector ? LOG : WARNING,
    5541             :                     (errcode_for_file_access(),
    5542             :                      errmsg("could not open statistics file \"%s\": %m",
    5543             :                             statfile)));
    5544        1592 :         return false;
    5545             :     }
    5546             : 
    5547             :     /*
    5548             :      * Verify it's of the expected format.
    5549             :      */
    5550        8588 :     if (fread(&format_id, 1, sizeof(format_id), fpin) != sizeof(format_id) ||
    5551        4294 :         format_id != PGSTAT_FILE_FORMAT_ID)
    5552             :     {
    5553           0 :         ereport(pgStatRunningInCollector ? LOG : WARNING,
    5554             :                 (errmsg("corrupted statistics file \"%s\"", statfile)));
    5555           0 :         FreeFile(fpin);
    5556           0 :         return false;
    5557             :     }
    5558             : 
    5559             :     /*
    5560             :      * Read global stats struct
    5561             :      */
    5562        4294 :     if (fread(&myGlobalStats, 1, sizeof(myGlobalStats),
    5563             :               fpin) != sizeof(myGlobalStats))
    5564             :     {
    5565           0 :         ereport(pgStatRunningInCollector ? LOG : WARNING,
    5566             :                 (errmsg("corrupted statistics file \"%s\"", statfile)));
    5567           0 :         FreeFile(fpin);
    5568           0 :         return false;
    5569             :     }
    5570             : 
    5571             :     /*
    5572             :      * Read archiver stats struct
    5573             :      */
    5574        4294 :     if (fread(&myArchiverStats, 1, sizeof(myArchiverStats),
    5575             :               fpin) != sizeof(myArchiverStats))
    5576             :     {
    5577           0 :         ereport(pgStatRunningInCollector ? LOG : WARNING,
    5578             :                 (errmsg("corrupted statistics file \"%s\"", statfile)));
    5579           0 :         FreeFile(fpin);
    5580           0 :         return false;
    5581             :     }
    5582             : 
    5583             :     /* By default, we're going to return the timestamp of the global file. */
    5584        4294 :     *ts = myGlobalStats.stats_timestamp;
    5585             : 
    5586             :     /*
    5587             :      * We found an existing collector stats file.  Read it and look for a
    5588             :      * record for the requested database.  If found, use its timestamp.
    5589             :      */
    5590             :     for (;;)
    5591             :     {
    5592        5814 :         switch (fgetc(fpin))
    5593             :         {
    5594             :                 /*
    5595             :                  * 'D'  A PgStat_StatDBEntry struct describing a database
    5596             :                  * follows.
    5597             :                  */
    5598             :             case 'D':
    5599        4046 :                 if (fread(&dbentry, 1, offsetof(PgStat_StatDBEntry, tables),
    5600             :                           fpin) != offsetof(PgStat_StatDBEntry, tables))
    5601             :                 {
    5602           0 :                     ereport(pgStatRunningInCollector ? LOG : WARNING,
    5603             :                             (errmsg("corrupted statistics file \"%s\"",
    5604             :                                     statfile)));
    5605           0 :                     goto done;
    5606             :                 }
    5607             : 
    5608             :                 /*
    5609             :                  * If this is the DB we're looking for, save its timestamp and
    5610             :                  * we're done.
    5611             :                  */
    5612        4046 :                 if (dbentry.databaseid == databaseid)
    5613             :                 {
    5614        3286 :                     *ts = dbentry.stats_timestamp;
    5615        3286 :                     goto done;
    5616             :                 }
    5617             : 
    5618         760 :                 break;
    5619             : 
    5620             :             case 'E':
    5621        1008 :                 goto done;
    5622             : 
    5623             :             default:
    5624           0 :                 ereport(pgStatRunningInCollector ? LOG : WARNING,
    5625             :                         (errmsg("corrupted statistics file \"%s\"",
    5626             :                                 statfile)));
    5627           0 :                 goto done;
    5628             :         }
    5629             :     }
    5630             : 
    5631             : done:
    5632        4294 :     FreeFile(fpin);
    5633        4294 :     return true;
    5634             : }
    5635             : 
    5636             : /*
    5637             :  * If not already done, read the statistics collector stats file into
    5638             :  * some hash tables.  The results will be kept until pgstat_clear_snapshot()
    5639             :  * is called (typically, at end of transaction).
    5640             :  */
    5641             : static void
    5642        6356 : backend_read_statsfile(void)
    5643             : {
    5644        6356 :     TimestampTz min_ts = 0;
    5645        6356 :     TimestampTz ref_ts = 0;
    5646             :     Oid         inquiry_db;
    5647             :     int         count;
    5648             : 
    5649             :     /* already read it? */
    5650        6356 :     if (pgStatDBHash)
    5651        2744 :         return;
    5652             :     Assert(!pgStatRunningInCollector);
    5653             : 
    5654             :     /*
    5655             :      * In a normal backend, we check staleness of the data for our own DB, and
    5656             :      * so we send MyDatabaseId in inquiry messages.  In the autovac launcher,
    5657             :      * check staleness of the shared-catalog data, and send InvalidOid in
    5658             :      * inquiry messages so as not to force writing unnecessary data.
    5659             :      */
    5660        3612 :     if (IsAutoVacuumLauncherProcess())
    5661         712 :         inquiry_db = InvalidOid;
    5662             :     else
    5663        2900 :         inquiry_db = MyDatabaseId;
    5664             : 
    5665             :     /*
    5666             :      * Loop until fresh enough stats file is available or we ran out of time.
    5667             :      * The stats inquiry message is sent repeatedly in case collector drops
    5668             :      * it; but not every single time, as that just swamps the collector.
    5669             :      */
    5670       11772 :     for (count = 0; count < PGSTAT_POLL_LOOP_COUNT; count++)
    5671             :     {
    5672             :         bool        ok;
    5673        5886 :         TimestampTz file_ts = 0;
    5674             :         TimestampTz cur_ts;
    5675             : 
    5676        5886 :         CHECK_FOR_INTERRUPTS();
    5677             : 
    5678        5886 :         ok = pgstat_read_db_statsfile_timestamp(inquiry_db, false, &file_ts);
    5679             : 
    5680        5886 :         cur_ts = GetCurrentTimestamp();
    5681             :         /* Calculate min acceptable timestamp, if we didn't already */
    5682        5886 :         if (count == 0 || cur_ts < ref_ts)
    5683             :         {
    5684             :             /*
    5685             :              * We set the minimum acceptable timestamp to PGSTAT_STAT_INTERVAL
    5686             :              * msec before now.  This indirectly ensures that the collector
    5687             :              * needn't write the file more often than PGSTAT_STAT_INTERVAL. In
    5688             :              * an autovacuum worker, however, we want a lower delay to avoid
    5689             :              * using stale data, so we use PGSTAT_RETRY_DELAY (since the
    5690             :              * number of workers is low, this shouldn't be a problem).
    5691             :              *
    5692             :              * We don't recompute min_ts after sleeping, except in the
    5693             :              * unlikely case that cur_ts went backwards.  So we might end up
    5694             :              * accepting a file a bit older than PGSTAT_STAT_INTERVAL.  In
    5695             :              * practice that shouldn't happen, though, as long as the sleep
    5696             :              * time is less than PGSTAT_STAT_INTERVAL; and we don't want to
    5697             :              * tell the collector that our cutoff time is less than what we'd
    5698             :              * actually accept.
    5699             :              */
    5700        3612 :             ref_ts = cur_ts;
    5701        3612 :             if (IsAutoVacuumWorkerProcess())
    5702         460 :                 min_ts = TimestampTzPlusMilliseconds(ref_ts,
    5703             :                                                      -PGSTAT_RETRY_DELAY);
    5704             :             else
    5705        3152 :                 min_ts = TimestampTzPlusMilliseconds(ref_ts,
    5706             :                                                      -PGSTAT_STAT_INTERVAL);
    5707             :         }
    5708             : 
    5709             :         /*
    5710             :          * If the file timestamp is actually newer than cur_ts, we must have
    5711             :          * had a clock glitch (system time went backwards) or there is clock
    5712             :          * skew between our processor and the stats collector's processor.
    5713             :          * Accept the file, but send an inquiry message anyway to make
    5714             :          * pgstat_recv_inquiry do a sanity check on the collector's time.
    5715             :          */
    5716        5886 :         if (ok && file_ts > cur_ts)
    5717             :         {
    5718             :             /*
    5719             :              * A small amount of clock skew between processors isn't terribly
    5720             :              * surprising, but a large difference is worth logging.  We
    5721             :              * arbitrarily define "large" as 1000 msec.
    5722             :              */
    5723           0 :             if (file_ts >= TimestampTzPlusMilliseconds(cur_ts, 1000))
    5724             :             {
    5725             :                 char       *filetime;
    5726             :                 char       *mytime;
    5727             : 
    5728             :                 /* Copy because timestamptz_to_str returns a static buffer */
    5729           0 :                 filetime = pstrdup(timestamptz_to_str(file_ts));
    5730           0 :                 mytime = pstrdup(timestamptz_to_str(cur_ts));
    5731           0 :                 elog(LOG, "stats collector's time %s is later than backend local time %s",
    5732             :                      filetime, mytime);
    5733           0 :                 pfree(filetime);
    5734           0 :                 pfree(mytime);
    5735             :             }
    5736             : 
    5737           0 :             pgstat_send_inquiry(cur_ts, min_ts, inquiry_db);
    5738           0 :             break;
    5739             :         }
    5740             : 
    5741             :         /* Normal acceptance case: file is not older than cutoff time */
    5742        5886 :         if (ok && file_ts >= min_ts)
    5743        3612 :             break;
    5744             : 
    5745             :         /* Not there or too old, so kick the collector and wait a bit */
    5746        2274 :         if ((count % PGSTAT_INQ_LOOP_COUNT) == 0)
    5747        1032 :             pgstat_send_inquiry(cur_ts, min_ts, inquiry_db);
    5748             : 
    5749        2274 :         pg_usleep(PGSTAT_RETRY_DELAY * 1000L);
    5750             :     }
    5751             : 
    5752        3612 :     if (count >= PGSTAT_POLL_LOOP_COUNT)
    5753           0 :         ereport(LOG,
    5754             :                 (errmsg("using stale statistics instead of current ones "
    5755             :                         "because stats collector is not responding")));
    5756             : 
    5757             :     /*
    5758             :      * Autovacuum launcher wants stats about all databases, but a shallow read
    5759             :      * is sufficient.  Regular backends want a deep read for just the tables
    5760             :      * they can see (MyDatabaseId + shared catalogs).
    5761             :      */
    5762        3612 :     if (IsAutoVacuumLauncherProcess())
    5763         712 :         pgStatDBHash = pgstat_read_statsfiles(InvalidOid, false, false);
    5764             :     else
    5765        2900 :         pgStatDBHash = pgstat_read_statsfiles(MyDatabaseId, false, true);
    5766             : }
    5767             : 
    5768             : 
    5769             : /* ----------
    5770             :  * pgstat_setup_memcxt() -
    5771             :  *
    5772             :  *  Create pgStatLocalContext, if not already done.
    5773             :  * ----------
    5774             :  */
    5775             : static void
    5776        4398 : pgstat_setup_memcxt(void)
    5777             : {
    5778        4398 :     if (!pgStatLocalContext)
    5779        4398 :         pgStatLocalContext = AllocSetContextCreate(TopMemoryContext,
    5780             :                                                    "Statistics snapshot",
    5781             :                                                    ALLOCSET_SMALL_SIZES);
    5782        4398 : }
    5783             : 
    5784             : 
    5785             : /* ----------
    5786             :  * pgstat_clear_snapshot() -
    5787             :  *
    5788             :  *  Discard any data collected in the current transaction.  Any subsequent
    5789             :  *  request will cause new snapshots to be read.
    5790             :  *
    5791             :  *  This is also invoked during transaction commit or abort to discard
    5792             :  *  the no-longer-wanted snapshot.
    5793             :  * ----------
    5794             :  */
    5795             : void
    5796      461348 : pgstat_clear_snapshot(void)
    5797             : {
    5798             :     /* Release memory, if any was allocated */
    5799      461348 :     if (pgStatLocalContext)
    5800        3488 :         MemoryContextDelete(pgStatLocalContext);
    5801             : 
    5802             :     /* Reset variables */
    5803      461348 :     pgStatLocalContext = NULL;
    5804      461348 :     pgStatDBHash = NULL;
    5805      461348 :     localBackendStatusTable = NULL;
    5806      461348 :     localNumBackends = 0;
    5807      461348 : }
    5808             : 
    5809             : 
    5810             : /* ----------
    5811             :  * pgstat_recv_inquiry() -
    5812             :  *
    5813             :  *  Process stat inquiry requests.
    5814             :  * ----------
    5815             :  */
    5816             : static void
    5817        1186 : pgstat_recv_inquiry(PgStat_MsgInquiry *msg, int len)
    5818             : {
    5819             :     PgStat_StatDBEntry *dbentry;
    5820             : 
    5821        1186 :     elog(DEBUG2, "received inquiry for database %u", msg->databaseid);
    5822             : 
    5823             :     /*
    5824             :      * If there's already a write request for this DB, there's nothing to do.
    5825             :      *
    5826             :      * Note that if a request is found, we return early and skip the below
    5827             :      * check for clock skew.  This is okay, since the only way for a DB
    5828             :      * request to be present in the list is that we have been here since the
    5829             :      * last write round.  It seems sufficient to check for clock skew once per
    5830             :      * write round.
    5831             :      */
    5832        1186 :     if (list_member_oid(pending_write_requests, msg->databaseid))
    5833           0 :         return;
    5834             : 
    5835             :     /*
    5836             :      * Check to see if we last wrote this database at a time >= the requested
    5837             :      * cutoff time.  If so, this is a stale request that was generated before
    5838             :      * we updated the DB file, and we don't need to do so again.
    5839             :      *
    5840             :      * If the requestor's local clock time is older than stats_timestamp, we
    5841             :      * should suspect a clock glitch, ie system time going backwards; though
    5842             :      * the more likely explanation is just delayed message receipt.  It is
    5843             :      * worth expending a GetCurrentTimestamp call to be sure, since a large
    5844             :      * retreat in the system clock reading could otherwise cause us to neglect
    5845             :      * to update the stats file for a long time.
    5846             :      */
    5847        1186 :     dbentry = pgstat_get_db_entry(msg->databaseid, false);
    5848        1186 :     if (dbentry == NULL)
    5849             :     {
    5850             :         /*
    5851             :          * We have no data for this DB.  Enter a write request anyway so that
    5852             :          * the global stats will get updated.  This is needed to prevent
    5853             :          * backend_read_statsfile from waiting for data that we cannot supply,
    5854             :          * in the case of a new DB that nobody has yet reported any stats for.
    5855             :          * See the behavior of pgstat_read_db_statsfile_timestamp.
    5856             :          */
    5857             :     }
    5858         828 :     else if (msg->clock_time < dbentry->stats_timestamp)
    5859             :     {
    5860           0 :         TimestampTz cur_ts = GetCurrentTimestamp();
    5861             : 
    5862           0 :         if (cur_ts < dbentry->stats_timestamp)
    5863             :         {
    5864             :             /*
    5865             :              * Sure enough, time went backwards.  Force a new stats file write
    5866             :              * to get back in sync; but first, log a complaint.
    5867             :              */
    5868             :             char       *writetime;
    5869             :             char       *mytime;
    5870             : 
    5871             :             /* Copy because timestamptz_to_str returns a static buffer */
    5872           0 :             writetime = pstrdup(timestamptz_to_str(dbentry->stats_timestamp));
    5873           0 :             mytime = pstrdup(timestamptz_to_str(cur_ts));
    5874           0 :             elog(LOG,
    5875             :                  "stats_timestamp %s is later than collector's time %s for database %u",
    5876             :                  writetime, mytime, dbentry->databaseid);
    5877           0 :             pfree(writetime);
    5878           0 :             pfree(mytime);
    5879             :         }
    5880             :         else
    5881             :         {
    5882             :             /*
    5883             :              * Nope, it's just an old request.  Assuming msg's clock_time is
    5884             :              * >= its cutoff_time, it must be stale, so we can ignore it.
    5885             :              */
    5886           0 :             return;
    5887             :         }
    5888             :     }
    5889         828 :     else if (msg->cutoff_time <= dbentry->stats_timestamp)
    5890             :     {
    5891             :         /* Stale request, ignore it */
    5892           0 :         return;
    5893             :     }
    5894             : 
    5895             :     /*
    5896             :      * We need to write this DB, so create a request.
    5897             :      */
    5898        1186 :     pending_write_requests = lappend_oid(pending_write_requests,
    5899             :                                          msg->databaseid);
    5900             : }
    5901             : 
    5902             : 
    5903             : /* ----------
    5904             :  * pgstat_recv_tabstat() -
    5905             :  *
    5906             :  *  Count what the backend has done.
    5907             :  * ----------
    5908             :  */
    5909             : static void
    5910       74976 : pgstat_recv_tabstat(PgStat_MsgTabstat *msg, int len)
    5911             : {
    5912             :     PgStat_StatDBEntry *dbentry;
    5913             :     PgStat_StatTabEntry *tabentry;
    5914             :     int         i;
    5915             :     bool        found;
    5916             : 
    5917       74976 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    5918             : 
    5919             :     /*
    5920             :      * Update database-wide stats.
    5921             :      */
    5922       74976 :     dbentry->n_xact_commit += (PgStat_Counter) (msg->m_xact_commit);
    5923       74976 :     dbentry->n_xact_rollback += (PgStat_Counter) (msg->m_xact_rollback);
    5924       74976 :     dbentry->n_block_read_time += msg->m_block_read_time;
    5925       74976 :     dbentry->n_block_write_time += msg->m_block_write_time;
    5926             : 
    5927             :     /*
    5928             :      * Process all table entries in the message.
    5929             :      */
    5930      571728 :     for (i = 0; i < msg->m_nentries; i++)
    5931             :     {
    5932      496752 :         PgStat_TableEntry *tabmsg = &(msg->m_entry[i]);
    5933             : 
    5934      496752 :         tabentry = (PgStat_StatTabEntry *) hash_search(dbentry->tables,
    5935      496752 :                                                        (void *) &(tabmsg->t_id),
    5936             :                                                        HASH_ENTER, &found);
    5937             : 
    5938      496752 :         if (!found)
    5939             :         {
    5940             :             /*
    5941             :              * If it's a new table entry, initialize counters to the values we
    5942             :              * just got.
    5943             :              */
    5944       61104 :             tabentry->numscans = tabmsg->t_counts.t_numscans;
    5945       61104 :             tabentry->tuples_returned = tabmsg->t_counts.t_tuples_returned;
    5946       61104 :             tabentry->tuples_fetched = tabmsg->t_counts.t_tuples_fetched;
    5947       61104 :             tabentry->tuples_inserted = tabmsg->t_counts.t_tuples_inserted;
    5948       61104 :             tabentry->tuples_updated = tabmsg->t_counts.t_tuples_updated;
    5949       61104 :             tabentry->tuples_deleted = tabmsg->t_counts.t_tuples_deleted;
    5950       61104 :             tabentry->tuples_hot_updated = tabmsg->t_counts.t_tuples_hot_updated;
    5951       61104 :             tabentry->n_live_tuples = tabmsg->t_counts.t_delta_live_tuples;
    5952       61104 :             tabentry->n_dead_tuples = tabmsg->t_counts.t_delta_dead_tuples;
    5953       61104 :             tabentry->changes_since_analyze = tabmsg->t_counts.t_changed_tuples;
    5954       61104 :             tabentry->blocks_fetched = tabmsg->t_counts.t_blocks_fetched;
    5955       61104 :             tabentry->blocks_hit = tabmsg->t_counts.t_blocks_hit;
    5956             : 
    5957       61104 :             tabentry->vacuum_timestamp = 0;
    5958       61104 :             tabentry->vacuum_count = 0;
    5959       61104 :             tabentry->autovac_vacuum_timestamp = 0;
    5960       61104 :             tabentry->autovac_vacuum_count = 0;
    5961       61104 :             tabentry->analyze_timestamp = 0;
    5962       61104 :             tabentry->analyze_count = 0;
    5963       61104 :             tabentry->autovac_analyze_timestamp = 0;
    5964       61104 :             tabentry->autovac_analyze_count = 0;
    5965             :         }
    5966             :         else
    5967             :         {
    5968             :             /*
    5969             :              * Otherwise add the values to the existing entry.
    5970             :              */
    5971      435648 :             tabentry->numscans += tabmsg->t_counts.t_numscans;
    5972      435648 :             tabentry->tuples_returned += tabmsg->t_counts.t_tuples_returned;
    5973      435648 :             tabentry->tuples_fetched += tabmsg->t_counts.t_tuples_fetched;
    5974      435648 :             tabentry->tuples_inserted += tabmsg->t_counts.t_tuples_inserted;
    5975      435648 :             tabentry->tuples_updated += tabmsg->t_counts.t_tuples_updated;
    5976      435648 :             tabentry->tuples_deleted += tabmsg->t_counts.t_tuples_deleted;
    5977      435648 :             tabentry->tuples_hot_updated += tabmsg->t_counts.t_tuples_hot_updated;
    5978             :             /* If table was truncated, first reset the live/dead counters */
    5979      435648 :             if (tabmsg->t_counts.t_truncated)
    5980             :             {
    5981         142 :                 tabentry->n_live_tuples = 0;
    5982         142 :                 tabentry->n_dead_tuples = 0;
    5983             :             }
    5984      435648 :             tabentry->n_live_tuples += tabmsg->t_counts.t_delta_live_tuples;
    5985      435648 :             tabentry->n_dead_tuples += tabmsg->t_counts.t_delta_dead_tuples;
    5986      435648 :             tabentry->changes_since_analyze += tabmsg->t_counts.t_changed_tuples;
    5987      435648 :             tabentry->blocks_fetched += tabmsg->t_counts.t_blocks_fetched;
    5988      435648 :             tabentry->blocks_hit += tabmsg->t_counts.t_blocks_hit;
    5989             :         }
    5990             : 
    5991             :         /* Clamp n_live_tuples in case of negative delta_live_tuples */
    5992      496752 :         tabentry->n_live_tuples = Max(tabentry->n_live_tuples, 0);
    5993             :         /* Likewise for n_dead_tuples */
    5994      496752 :         tabentry->n_dead_tuples = Max(tabentry->n_dead_tuples, 0);
    5995             : 
    5996             :         /*
    5997             :          * Add per-table stats to the per-database entry, too.
    5998             :          */
    5999      496752 :         dbentry->n_tuples_returned += tabmsg->t_counts.t_tuples_returned;
    6000      496752 :         dbentry->n_tuples_fetched += tabmsg->t_counts.t_tuples_fetched;
    6001      496752 :         dbentry->n_tuples_inserted += tabmsg->t_counts.t_tuples_inserted;
    6002      496752 :         dbentry->n_tuples_updated += tabmsg->t_counts.t_tuples_updated;
    6003      496752 :         dbentry->n_tuples_deleted += tabmsg->t_counts.t_tuples_deleted;
    6004      496752 :         dbentry->n_blocks_fetched += tabmsg->t_counts.t_blocks_fetched;
    6005      496752 :         dbentry->n_blocks_hit += tabmsg->t_counts.t_blocks_hit;
    6006             :     }
    6007       74976 : }
    6008             : 
    6009             : 
    6010             : /* ----------
    6011             :  * pgstat_recv_tabpurge() -
    6012             :  *
    6013             :  *  Arrange for dead table removal.
    6014             :  * ----------
    6015             :  */
    6016             : static void
    6017         898 : pgstat_recv_tabpurge(PgStat_MsgTabpurge *msg, int len)
    6018             : {
    6019             :     PgStat_StatDBEntry *dbentry;
    6020             :     int         i;
    6021             : 
    6022         898 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, false);
    6023             : 
    6024             :     /*
    6025             :      * No need to purge if we don't even know the database.
    6026             :      */
    6027         898 :     if (!dbentry || !dbentry->tables)
    6028           0 :         return;
    6029             : 
    6030             :     /*
    6031             :      * Process all table entries in the message.
    6032             :      */
    6033       93068 :     for (i = 0; i < msg->m_nentries; i++)
    6034             :     {
    6035             :         /* Remove from hashtable if present; we don't care if it's not. */
    6036       92170 :         (void) hash_search(dbentry->tables,
    6037       92170 :                            (void *) &(msg->m_tableid[i]),
    6038             :                            HASH_REMOVE, NULL);
    6039             :     }
    6040             : }
    6041             : 
    6042             : 
    6043             : /* ----------
    6044             :  * pgstat_recv_dropdb() -
    6045             :  *
    6046             :  *  Arrange for dead database removal
    6047             :  * ----------
    6048             :  */
    6049             : static void
    6050          16 : pgstat_recv_dropdb(PgStat_MsgDropdb *msg, int len)
    6051             : {
    6052          16 :     Oid         dbid = msg->m_databaseid;
    6053             :     PgStat_StatDBEntry *dbentry;
    6054             : 
    6055             :     /*
    6056             :      * Lookup the database in the hashtable.
    6057             :      */
    6058          16 :     dbentry = pgstat_get_db_entry(dbid, false);
    6059             : 
    6060             :     /*
    6061             :      * If found, remove it (along with the db statfile).
    6062             :      */
    6063          16 :     if (dbentry)
    6064             :     {
    6065             :         char        statfile[MAXPGPATH];
    6066             : 
    6067          10 :         get_dbstat_filename(false, false, dbid, statfile, MAXPGPATH);
    6068             : 
    6069          10 :         elog(DEBUG2, "removing stats file \"%s\"", statfile);
    6070          10 :         unlink(statfile);
    6071             : 
    6072          10 :         if (dbentry->tables != NULL)
    6073          10 :             hash_destroy(dbentry->tables);
    6074          10 :         if (dbentry->functions != NULL)
    6075          10 :             hash_destroy(dbentry->functions);
    6076             : 
    6077          10 :         if (hash_search(pgStatDBHash,
    6078             :                         (void *) &dbid,
    6079             :                         HASH_REMOVE, NULL) == NULL)
    6080           0 :             ereport(ERROR,
    6081             :                     (errmsg("database hash table corrupted during cleanup --- abort")));
    6082             :     }
    6083          16 : }
    6084             : 
    6085             : 
    6086             : /* ----------
    6087             :  * pgstat_recv_resetcounter() -
    6088             :  *
    6089             :  *  Reset the statistics for the specified database.
    6090             :  * ----------
    6091             :  */
    6092             : static void
    6093           0 : pgstat_recv_resetcounter(PgStat_MsgResetcounter *msg, int len)
    6094             : {
    6095             :     PgStat_StatDBEntry *dbentry;
    6096             : 
    6097             :     /*
    6098             :      * Lookup the database in the hashtable.  Nothing to do if not there.
    6099             :      */
    6100           0 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, false);
    6101             : 
    6102           0 :     if (!dbentry)
    6103           0 :         return;
    6104             : 
    6105             :     /*
    6106             :      * We simply throw away all the database's table entries by recreating a
    6107             :      * new hash table for them.
    6108             :      */
    6109           0 :     if (dbentry->tables != NULL)
    6110           0 :         hash_destroy(dbentry->tables);
    6111           0 :     if (dbentry->functions != NULL)
    6112           0 :         hash_destroy(dbentry->functions);
    6113             : 
    6114           0 :     dbentry->tables = NULL;
    6115           0 :     dbentry->functions = NULL;
    6116             : 
    6117             :     /*
    6118             :      * Reset database-level stats, too.  This creates empty hash tables for
    6119             :      * tables and functions.
    6120             :      */
    6121           0 :     reset_dbentry_counters(dbentry);
    6122             : }
    6123             : 
    6124             : /* ----------
    6125             :  * pgstat_recv_resetshared() -
    6126             :  *
    6127             :  *  Reset some shared statistics of the cluster.
    6128             :  * ----------
    6129             :  */
    6130             : static void
    6131           0 : pgstat_recv_resetsharedcounter(PgStat_MsgResetsharedcounter *msg, int len)
    6132             : {
    6133           0 :     if (msg->m_resettarget == RESET_BGWRITER)
    6134             :     {
    6135             :         /* Reset the global background writer statistics for the cluster. */
    6136           0 :         memset(&globalStats, 0, sizeof(globalStats));
    6137           0 :         globalStats.stat_reset_timestamp = GetCurrentTimestamp();
    6138             :     }
    6139           0 :     else if (msg->m_resettarget == RESET_ARCHIVER)
    6140             :     {
    6141             :         /* Reset the archiver statistics for the cluster. */
    6142           0 :         memset(&archiverStats, 0, sizeof(archiverStats));
    6143           0 :         archiverStats.stat_reset_timestamp = GetCurrentTimestamp();
    6144             :     }
    6145             : 
    6146             :     /*
    6147             :      * Presumably the sender of this message validated the target, don't
    6148             :      * complain here if it's not valid
    6149             :      */
    6150           0 : }
    6151             : 
    6152             : /* ----------
    6153             :  * pgstat_recv_resetsinglecounter() -
    6154             :  *
    6155             :  *  Reset a statistics for a single object
    6156             :  * ----------
    6157             :  */
    6158             : static void
    6159           0 : pgstat_recv_resetsinglecounter(PgStat_MsgResetsinglecounter *msg, int len)
    6160             : {
    6161             :     PgStat_StatDBEntry *dbentry;
    6162             : 
    6163           0 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, false);
    6164             : 
    6165           0 :     if (!dbentry)
    6166           0 :         return;
    6167             : 
    6168             :     /* Set the reset timestamp for the whole database */
    6169           0 :     dbentry->stat_reset_timestamp = GetCurrentTimestamp();
    6170             : 
    6171             :     /* Remove object if it exists, ignore it if not */
    6172           0 :     if (msg->m_resettype == RESET_TABLE)
    6173           0 :         (void) hash_search(dbentry->tables, (void *) &(msg->m_objectid),
    6174             :                            HASH_REMOVE, NULL);
    6175           0 :     else if (msg->m_resettype == RESET_FUNCTION)
    6176           0 :         (void) hash_search(dbentry->functions, (void *) &(msg->m_objectid),
    6177             :                            HASH_REMOVE, NULL);
    6178             : }
    6179             : 
    6180             : /* ----------
    6181             :  * pgstat_recv_autovac() -
    6182             :  *
    6183             :  *  Process an autovacuum signalling message.
    6184             :  * ----------
    6185             :  */
    6186             : static void
    6187          64 : pgstat_recv_autovac(PgStat_MsgAutovacStart *msg, int len)
    6188             : {
    6189             :     PgStat_StatDBEntry *dbentry;
    6190             : 
    6191             :     /*
    6192             :      * Store the last autovacuum time in the database's hashtable entry.
    6193             :      */
    6194          64 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6195             : 
    6196          64 :     dbentry->last_autovac_time = msg->m_start_time;
    6197          64 : }
    6198             : 
    6199             : /* ----------
    6200             :  * pgstat_recv_vacuum() -
    6201             :  *
    6202             :  *  Process a VACUUM message.
    6203             :  * ----------
    6204             :  */
    6205             : static void
    6206        4568 : pgstat_recv_vacuum(PgStat_MsgVacuum *msg, int len)
    6207             : {
    6208             :     PgStat_StatDBEntry *dbentry;
    6209             :     PgStat_StatTabEntry *tabentry;
    6210             : 
    6211             :     /*
    6212             :      * Store the data in the table's hashtable entry.
    6213             :      */
    6214        4568 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6215             : 
    6216        4568 :     tabentry = pgstat_get_tab_entry(dbentry, msg->m_tableoid, true);
    6217             : 
    6218        4568 :     tabentry->n_live_tuples = msg->m_live_tuples;
    6219        4568 :     tabentry->n_dead_tuples = msg->m_dead_tuples;
    6220             : 
    6221        4568 :     if (msg->m_autovacuum)
    6222             :     {
    6223         194 :         tabentry->autovac_vacuum_timestamp = msg->m_vacuumtime;
    6224         194 :         tabentry->autovac_vacuum_count++;
    6225             :     }
    6226             :     else
    6227             :     {
    6228        4374 :         tabentry->vacuum_timestamp = msg->m_vacuumtime;
    6229        4374 :         tabentry->vacuum_count++;
    6230             :     }
    6231        4568 : }
    6232             : 
    6233             : /* ----------
    6234             :  * pgstat_recv_analyze() -
    6235             :  *
    6236             :  *  Process an ANALYZE message.
    6237             :  * ----------
    6238             :  */
    6239             : static void
    6240        9640 : pgstat_recv_analyze(PgStat_MsgAnalyze *msg, int len)
    6241             : {
    6242             :     PgStat_StatDBEntry *dbentry;
    6243             :     PgStat_StatTabEntry *tabentry;
    6244             : 
    6245             :     /*
    6246             :      * Store the data in the table's hashtable entry.
    6247             :      */
    6248        9640 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6249             : 
    6250        9640 :     tabentry = pgstat_get_tab_entry(dbentry, msg->m_tableoid, true);
    6251             : 
    6252        9640 :     tabentry->n_live_tuples = msg->m_live_tuples;
    6253        9640 :     tabentry->n_dead_tuples = msg->m_dead_tuples;
    6254             : 
    6255             :     /*
    6256             :      * If commanded, reset changes_since_analyze to zero.  This forgets any
    6257             :      * changes that were committed while the ANALYZE was in progress, but we
    6258             :      * have no good way to estimate how many of those there were.
    6259             :      */
    6260        9640 :     if (msg->m_resetcounter)
    6261        9616 :         tabentry->changes_since_analyze = 0;
    6262             : 
    6263        9640 :     if (msg->m_autovacuum)
    6264             :     {
    6265         366 :         tabentry->autovac_analyze_timestamp = msg->m_analyzetime;
    6266         366 :         tabentry->autovac_analyze_count++;
    6267             :     }
    6268             :     else
    6269             :     {
    6270        9274 :         tabentry->analyze_timestamp = msg->m_analyzetime;
    6271        9274 :         tabentry->analyze_count++;
    6272             :     }
    6273        9640 : }
    6274             : 
    6275             : 
    6276             : /* ----------
    6277             :  * pgstat_recv_archiver() -
    6278             :  *
    6279             :  *  Process a ARCHIVER message.
    6280             :  * ----------
    6281             :  */
    6282             : static void
    6283          26 : pgstat_recv_archiver(PgStat_MsgArchiver *msg, int len)
    6284             : {
    6285          26 :     if (msg->m_failed)
    6286             :     {
    6287             :         /* Failed archival attempt */
    6288           0 :         ++archiverStats.failed_count;
    6289           0 :         memcpy(archiverStats.last_failed_wal, msg->m_xlog,
    6290             :                sizeof(archiverStats.last_failed_wal));
    6291           0 :         archiverStats.last_failed_timestamp = msg->m_timestamp;
    6292             :     }
    6293             :     else
    6294             :     {
    6295             :         /* Successful archival operation */
    6296          26 :         ++archiverStats.archived_count;
    6297          26 :         memcpy(archiverStats.last_archived_wal, msg->m_xlog,
    6298             :                sizeof(archiverStats.last_archived_wal));
    6299          26 :         archiverStats.last_archived_timestamp = msg->m_timestamp;
    6300             :     }
    6301          26 : }
    6302             : 
    6303             : /* ----------
    6304             :  * pgstat_recv_bgwriter() -
    6305             :  *
    6306             :  *  Process a BGWRITER message.
    6307             :  * ----------
    6308             :  */
    6309             : static void
    6310        8140 : pgstat_recv_bgwriter(PgStat_MsgBgWriter *msg, int len)
    6311             : {
    6312        8140 :     globalStats.timed_checkpoints += msg->m_timed_checkpoints;
    6313        8140 :     globalStats.requested_checkpoints += msg->m_requested_checkpoints;
    6314        8140 :     globalStats.checkpoint_write_time += msg->m_checkpoint_write_time;
    6315        8140 :     globalStats.checkpoint_sync_time += msg->m_checkpoint_sync_time;
    6316        8140 :     globalStats.buf_written_checkpoints += msg->m_buf_written_checkpoints;
    6317        8140 :     globalStats.buf_written_clean += msg->m_buf_written_clean;
    6318        8140 :     globalStats.maxwritten_clean += msg->m_maxwritten_clean;
    6319        8140 :     globalStats.buf_written_backend += msg->m_buf_written_backend;
    6320        8140 :     globalStats.buf_fsync_backend += msg->m_buf_fsync_backend;
    6321        8140 :     globalStats.buf_alloc += msg->m_buf_alloc;
    6322        8140 : }
    6323             : 
    6324             : /* ----------
    6325             :  * pgstat_recv_recoveryconflict() -
    6326             :  *
    6327             :  *  Process a RECOVERYCONFLICT message.
    6328             :  * ----------
    6329             :  */
    6330             : static void
    6331           0 : pgstat_recv_recoveryconflict(PgStat_MsgRecoveryConflict *msg, int len)
    6332             : {
    6333             :     PgStat_StatDBEntry *dbentry;
    6334             : 
    6335           0 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6336             : 
    6337           0 :     switch (msg->m_reason)
    6338             :     {
    6339             :         case PROCSIG_RECOVERY_CONFLICT_DATABASE:
    6340             : 
    6341             :             /*
    6342             :              * Since we drop the information about the database as soon as it
    6343             :              * replicates, there is no point in counting these conflicts.
    6344             :              */
    6345           0 :             break;
    6346             :         case PROCSIG_RECOVERY_CONFLICT_TABLESPACE:
    6347           0 :             dbentry->n_conflict_tablespace++;
    6348           0 :             break;
    6349             :         case PROCSIG_RECOVERY_CONFLICT_LOCK:
    6350           0 :             dbentry->n_conflict_lock++;
    6351           0 :             break;
    6352             :         case PROCSIG_RECOVERY_CONFLICT_SNAPSHOT:
    6353           0 :             dbentry->n_conflict_snapshot++;
    6354           0 :             break;
    6355             :         case PROCSIG_RECOVERY_CONFLICT_BUFFERPIN:
    6356           0 :             dbentry->n_conflict_bufferpin++;
    6357           0 :             break;
    6358             :         case PROCSIG_RECOVERY_CONFLICT_STARTUP_DEADLOCK:
    6359           0 :             dbentry->n_conflict_startup_deadlock++;
    6360           0 :             break;
    6361             :     }
    6362           0 : }
    6363             : 
    6364             : /* ----------
    6365             :  * pgstat_recv_deadlock() -
    6366             :  *
    6367             :  *  Process a DEADLOCK message.
    6368             :  * ----------
    6369             :  */
    6370             : static void
    6371           4 : pgstat_recv_deadlock(PgStat_MsgDeadlock *msg, int len)
    6372             : {
    6373             :     PgStat_StatDBEntry *dbentry;
    6374             : 
    6375           4 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6376             : 
    6377           4 :     dbentry->n_deadlocks++;
    6378           4 : }
    6379             : 
    6380             : /* ----------
    6381             :  * pgstat_recv_checksum_failure() -
    6382             :  *
    6383             :  *  Process a CHECKSUMFAILURE message.
    6384             :  * ----------
    6385             :  */
    6386             : static void
    6387           4 : pgstat_recv_checksum_failure(PgStat_MsgChecksumFailure *msg, int len)
    6388             : {
    6389             :     PgStat_StatDBEntry *dbentry;
    6390             : 
    6391           4 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6392             : 
    6393           4 :     dbentry->n_checksum_failures += msg->m_failurecount;
    6394           4 :     dbentry->last_checksum_failure = msg->m_failure_time;
    6395           4 : }
    6396             : 
    6397             : /* ----------
    6398             :  * pgstat_recv_tempfile() -
    6399             :  *
    6400             :  *  Process a TEMPFILE message.
    6401             :  * ----------
    6402             :  */
    6403             : static void
    6404        3188 : pgstat_recv_tempfile(PgStat_MsgTempFile *msg, int len)
    6405             : {
    6406             :     PgStat_StatDBEntry *dbentry;
    6407             : 
    6408        3188 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6409             : 
    6410        3188 :     dbentry->n_temp_bytes += msg->m_filesize;
    6411        3188 :     dbentry->n_temp_files += 1;
    6412        3188 : }
    6413             : 
    6414             : /* ----------
    6415             :  * pgstat_recv_funcstat() -
    6416             :  *
    6417             :  *  Count what the backend has done.
    6418             :  * ----------
    6419             :  */
    6420             : static void
    6421           0 : pgstat_recv_funcstat(PgStat_MsgFuncstat *msg, int len)
    6422             : {
    6423           0 :     PgStat_FunctionEntry *funcmsg = &(msg->m_entry[0]);
    6424             :     PgStat_StatDBEntry *dbentry;
    6425             :     PgStat_StatFuncEntry *funcentry;
    6426             :     int         i;
    6427             :     bool        found;
    6428             : 
    6429           0 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, true);
    6430             : 
    6431             :     /*
    6432             :      * Process all function entries in the message.
    6433             :      */
    6434           0 :     for (i = 0; i < msg->m_nentries; i++, funcmsg++)
    6435             :     {
    6436           0 :         funcentry = (PgStat_StatFuncEntry *) hash_search(dbentry->functions,
    6437           0 :                                                          (void *) &(funcmsg->f_id),
    6438             :                                                          HASH_ENTER, &found);
    6439             : 
    6440           0 :         if (!found)
    6441             :         {
    6442             :             /*
    6443             :              * If it's a new function entry, initialize counters to the values
    6444             :              * we just got.
    6445             :              */
    6446           0 :             funcentry->f_numcalls = funcmsg->f_numcalls;
    6447           0 :             funcentry->f_total_time = funcmsg->f_total_time;
    6448           0 :             funcentry->f_self_time = funcmsg->f_self_time;
    6449             :         }
    6450             :         else
    6451             :         {
    6452             :             /*
    6453             :              * Otherwise add the values to the existing entry.
    6454             :              */
    6455           0 :             funcentry->f_numcalls += funcmsg->f_numcalls;
    6456           0 :             funcentry->f_total_time += funcmsg->f_total_time;
    6457           0 :             funcentry->f_self_time += funcmsg->f_self_time;
    6458             :         }
    6459             :     }
    6460           0 : }
    6461             : 
    6462             : /* ----------
    6463             :  * pgstat_recv_funcpurge() -
    6464             :  *
    6465             :  *  Arrange for dead function removal.
    6466             :  * ----------
    6467             :  */
    6468             : static void
    6469           0 : pgstat_recv_funcpurge(PgStat_MsgFuncpurge *msg, int len)
    6470             : {
    6471             :     PgStat_StatDBEntry *dbentry;
    6472             :     int         i;
    6473             : 
    6474           0 :     dbentry = pgstat_get_db_entry(msg->m_databaseid, false);
    6475             : 
    6476             :     /*
    6477             :      * No need to purge if we don't even know the database.
    6478             :      */
    6479           0 :     if (!dbentry || !dbentry->functions)
    6480           0 :         return;
    6481             : 
    6482             :     /*
    6483             :      * Process all function entries in the message.
    6484             :      */
    6485           0 :     for (i = 0; i < msg->m_nentries; i++)
    6486             :     {
    6487             :         /* Remove from hashtable if present; we don't care if it's not. */
    6488           0 :         (void) hash_search(dbentry->functions,
    6489           0 :                            (void *) &(msg->m_functionid[i]),
    6490             :                            HASH_REMOVE, NULL);
    6491             :     }
    6492             : }
    6493             : 
    6494             : /* ----------
    6495             :  * pgstat_write_statsfile_needed() -
    6496             :  *
    6497             :  *  Do we need to write out any stats files?
    6498             :  * ----------
    6499             :  */
    6500             : static bool
    6501      170752 : pgstat_write_statsfile_needed(void)
    6502             : {
    6503      170752 :     if (pending_write_requests != NIL)
    6504        1186 :         return true;
    6505             : 
    6506             :     /* Everything was written recently */
    6507      169566 :     return false;
    6508             : }
    6509             : 
    6510             : /* ----------
    6511             :  * pgstat_db_requested() -
    6512             :  *
    6513             :  *  Checks whether stats for a particular DB need to be written to a file.
    6514             :  * ----------
    6515             :  */
    6516             : static bool
    6517        2386 : pgstat_db_requested(Oid databaseid)
    6518             : {
    6519             :     /*
    6520             :      * If any requests are outstanding at all, we should write the stats for
    6521             :      * shared catalogs (the "database" with OID 0).  This ensures that
    6522             :      * backends will see up-to-date stats for shared catalogs, even though
    6523             :      * they send inquiry messages mentioning only their own DB.
    6524             :      */
    6525        2386 :     if (databaseid == InvalidOid && pending_write_requests != NIL)
    6526         828 :         return true;
    6527             : 
    6528             :     /* Search to see if there's an open request to write this database. */
    6529        1558 :     if (list_member_oid(pending_write_requests, databaseid))
    6530         638 :         return true;
    6531             : 
    6532         920 :     return false;
    6533             : }
    6534             : 
    6535             : /*
    6536             :  * Convert a potentially unsafely truncated activity string (see
    6537             :  * PgBackendStatus.st_activity_raw's documentation) into a correctly truncated
    6538             :  * one.
    6539             :  *
    6540             :  * The returned string is allocated in the caller's memory context and may be
    6541             :  * freed.
    6542             :  */
    6543             : char *
    6544        1510 : pgstat_clip_activity(const char *raw_activity)
    6545             : {
    6546             :     char       *activity;
    6547             :     int         rawlen;
    6548             :     int         cliplen;
    6549             : 
    6550             :     /*
    6551             :      * Some callers, like pgstat_get_backend_current_activity(), do not
    6552             :      * guarantee that the buffer isn't concurrently modified. We try to take
    6553             :      * care that the buffer is always terminated by a NUL byte regardless, but
    6554             :      * let's still be paranoid about the string's length. In those cases the
    6555             :      * underlying buffer is guaranteed to be pgstat_track_activity_query_size
    6556             :      * large.
    6557             :      */
    6558        1510 :     activity = pnstrdup(raw_activity, pgstat_track_activity_query_size - 1);
    6559             : 
    6560             :     /* now double-guaranteed to be NUL terminated */
    6561        1510 :     rawlen = strlen(activity);
    6562             : 
    6563             :     /*
    6564             :      * All supported server-encodings make it possible to determine the length
    6565             :      * of a multi-byte character from its first byte (this is not the case for
    6566             :      * client encodings, see GB18030). As st_activity is always stored using
    6567             :      * server encoding, this allows us to perform multi-byte aware truncation,
    6568             :      * even if the string earlier was truncated in the middle of a multi-byte
    6569             :      * character.
    6570             :      */
    6571        1510 :     cliplen = pg_mbcliplen(activity, rawlen,
    6572             :                            pgstat_track_activity_query_size - 1);
    6573             : 
    6574        1510 :     activity[cliplen] = '\0';
    6575             : 
    6576        1510 :     return activity;
    6577             : }

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