Branch data Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * postmaster.c
4 : : * This program acts as a clearing house for requests to the
5 : : * POSTGRES system. Frontend programs connect to the Postmaster,
6 : : * and postmaster forks a new backend process to handle the
7 : : * connection.
8 : : *
9 : : * The postmaster also manages system-wide operations such as
10 : : * startup and shutdown. The postmaster itself doesn't do those
11 : : * operations, mind you --- it just forks off a subprocess to do them
12 : : * at the right times. It also takes care of resetting the system
13 : : * if a backend crashes.
14 : : *
15 : : * The postmaster process creates the shared memory and semaphore
16 : : * pools during startup, but as a rule does not touch them itself.
17 : : * In particular, it is not a member of the PGPROC array of backends
18 : : * and so it cannot participate in lock-manager operations. Keeping
19 : : * the postmaster away from shared memory operations makes it simpler
20 : : * and more reliable. The postmaster is almost always able to recover
21 : : * from crashes of individual backends by resetting shared memory;
22 : : * if it did much with shared memory then it would be prone to crashing
23 : : * along with the backends.
24 : : *
25 : : * When a request message is received, we now fork() immediately.
26 : : * The child process performs authentication of the request, and
27 : : * then becomes a backend if successful. This allows the auth code
28 : : * to be written in a simple single-threaded style (as opposed to the
29 : : * crufty "poor man's multitasking" code that used to be needed).
30 : : * More importantly, it ensures that blockages in non-multithreaded
31 : : * libraries like SSL or PAM cannot cause denial of service to other
32 : : * clients.
33 : : *
34 : : *
35 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
36 : : * Portions Copyright (c) 1994, Regents of the University of California
37 : : *
38 : : *
39 : : * IDENTIFICATION
40 : : * src/backend/postmaster/postmaster.c
41 : : *
42 : : * NOTES
43 : : *
44 : : * Initialization:
45 : : * The Postmaster sets up shared memory data structures
46 : : * for the backends.
47 : : *
48 : : * Synchronization:
49 : : * The Postmaster shares memory with the backends but should avoid
50 : : * touching shared memory, so as not to become stuck if a crashing
51 : : * backend screws up locks or shared memory. Likewise, the Postmaster
52 : : * should never block on messages from frontend clients.
53 : : *
54 : : * Garbage Collection:
55 : : * The Postmaster cleans up after backends if they have an emergency
56 : : * exit and/or core dump.
57 : : *
58 : : * Error Reporting:
59 : : * Use write_stderr() only for reporting "interactive" errors
60 : : * (essentially, bogus arguments on the command line). Once the
61 : : * postmaster is launched, use ereport().
62 : : *
63 : : *-------------------------------------------------------------------------
64 : : */
65 : :
66 : : #include "postgres.h"
67 : :
68 : : #include <unistd.h>
69 : : #include <signal.h>
70 : : #include <time.h>
71 : : #include <sys/wait.h>
72 : : #include <ctype.h>
73 : : #include <sys/stat.h>
74 : : #include <sys/socket.h>
75 : : #include <fcntl.h>
76 : : #include <sys/param.h>
77 : : #include <netdb.h>
78 : : #include <limits.h>
79 : :
80 : : #ifdef USE_BONJOUR
81 : : #include <dns_sd.h>
82 : : #endif
83 : :
84 : : #ifdef USE_SYSTEMD
85 : : #include <systemd/sd-daemon.h>
86 : : #endif
87 : :
88 : : #ifdef HAVE_PTHREAD_IS_THREADED_NP
89 : : #include <pthread.h>
90 : : #endif
91 : :
92 : : #include "access/xlog.h"
93 : : #include "access/xlog_internal.h"
94 : : #include "access/xlogrecovery.h"
95 : : #include "common/file_perm.h"
96 : : #include "common/pg_prng.h"
97 : : #include "lib/ilist.h"
98 : : #include "libpq/libpq.h"
99 : : #include "libpq/pqsignal.h"
100 : : #include "pgstat.h"
101 : : #include "port/pg_bswap.h"
102 : : #include "port/pg_getopt_ctx.h"
103 : : #include "postmaster/autovacuum.h"
104 : : #include "postmaster/bgworker_internals.h"
105 : : #include "postmaster/pgarch.h"
106 : : #include "postmaster/postmaster.h"
107 : : #include "postmaster/syslogger.h"
108 : : #include "postmaster/walsummarizer.h"
109 : : #include "replication/logicallauncher.h"
110 : : #include "replication/slotsync.h"
111 : : #include "replication/walsender.h"
112 : : #include "storage/aio_subsys.h"
113 : : #include "storage/fd.h"
114 : : #include "storage/io_worker.h"
115 : : #include "storage/ipc.h"
116 : : #include "storage/pmsignal.h"
117 : : #include "storage/proc.h"
118 : : #include "storage/shmem_internal.h"
119 : : #include "tcop/backend_startup.h"
120 : : #include "tcop/tcopprot.h"
121 : : #include "utils/datetime.h"
122 : : #include "utils/memutils.h"
123 : : #include "utils/pidfile.h"
124 : : #include "utils/timestamp.h"
125 : : #include "utils/varlena.h"
126 : :
127 : : #ifdef EXEC_BACKEND
128 : : #include "common/file_utils.h"
129 : : #include "storage/pg_shmem.h"
130 : : #endif
131 : :
132 : :
133 : : /*
134 : : * CountChildren and SignalChildren take a bitmask argument to represent
135 : : * BackendTypes to count or signal. Define a separate type and functions to
136 : : * work with the bitmasks, to avoid accidentally passing a plain BackendType
137 : : * in place of a bitmask or vice versa.
138 : : */
139 : : typedef struct
140 : : {
141 : : uint32 mask;
142 : : } BackendTypeMask;
143 : :
144 : : StaticAssertDecl(BACKEND_NUM_TYPES < 32, "too many backend types for uint32");
145 : :
146 : : static const BackendTypeMask BTYPE_MASK_ALL = {(1 << BACKEND_NUM_TYPES) - 1};
147 : : static const BackendTypeMask BTYPE_MASK_NONE = {0};
148 : :
149 : : static inline BackendTypeMask
150 : 1773 : btmask(BackendType t)
151 : : {
152 : 1773 : BackendTypeMask mask = {.mask = 1 << t};
153 : :
154 : 1773 : return mask;
155 : : }
156 : :
157 : : static inline BackendTypeMask
158 : 18235 : btmask_add_n(BackendTypeMask mask, int nargs, BackendType *t)
159 : : {
160 [ + + ]: 80379 : for (int i = 0; i < nargs; i++)
161 : 62144 : mask.mask |= 1 << t[i];
162 : 18235 : return mask;
163 : : }
164 : :
165 : : #define btmask_add(mask, ...) \
166 : : btmask_add_n(mask, \
167 : : lengthof(((BackendType[]){__VA_ARGS__})), \
168 : : (BackendType[]){__VA_ARGS__} \
169 : : )
170 : :
171 : : static inline BackendTypeMask
172 : 5032 : btmask_del(BackendTypeMask mask, BackendType t)
173 : : {
174 : 5032 : mask.mask &= ~(1 << t);
175 : 5032 : return mask;
176 : : }
177 : :
178 : : static inline BackendTypeMask
179 : 2914 : btmask_all_except_n(int nargs, BackendType *t)
180 : : {
181 : 2914 : BackendTypeMask mask = BTYPE_MASK_ALL;
182 : :
183 [ + + ]: 7946 : for (int i = 0; i < nargs; i++)
184 : 5032 : mask = btmask_del(mask, t[i]);
185 : 2914 : return mask;
186 : : }
187 : :
188 : : #define btmask_all_except(...) \
189 : : btmask_all_except_n( \
190 : : lengthof(((BackendType[]){__VA_ARGS__})), \
191 : : (BackendType[]){__VA_ARGS__} \
192 : : )
193 : :
194 : : static inline bool
195 : 129009 : btmask_contains(BackendTypeMask mask, BackendType t)
196 : : {
197 : 129009 : return (mask.mask & (1 << t)) != 0;
198 : : }
199 : :
200 : :
201 : : BackgroundWorker *MyBgworkerEntry = NULL;
202 : :
203 : : /* The socket number we are listening for connections on */
204 : : int PostPortNumber = DEF_PGPORT;
205 : :
206 : : /* The directory names for Unix socket(s) */
207 : : char *Unix_socket_directories;
208 : :
209 : : /* The TCP listen address(es) */
210 : : char *ListenAddresses;
211 : :
212 : : /*
213 : : * SuperuserReservedConnections is the number of backends reserved for
214 : : * superuser use, and ReservedConnections is the number of backends reserved
215 : : * for use by roles with privileges of the pg_use_reserved_connections
216 : : * predefined role. These are taken out of the pool of MaxConnections backend
217 : : * slots, so the number of backend slots available for roles that are neither
218 : : * superuser nor have privileges of pg_use_reserved_connections is
219 : : * (MaxConnections - SuperuserReservedConnections - ReservedConnections).
220 : : *
221 : : * If the number of remaining slots is less than or equal to
222 : : * SuperuserReservedConnections, only superusers can make new connections. If
223 : : * the number of remaining slots is greater than SuperuserReservedConnections
224 : : * but less than or equal to
225 : : * (SuperuserReservedConnections + ReservedConnections), only superusers and
226 : : * roles with privileges of pg_use_reserved_connections can make new
227 : : * connections. Note that pre-existing superuser and
228 : : * pg_use_reserved_connections connections don't count against the limits.
229 : : */
230 : : int SuperuserReservedConnections;
231 : : int ReservedConnections;
232 : :
233 : : /* The socket(s) we're listening to. */
234 : : #define MAXLISTEN 64
235 : : static int NumListenSockets = 0;
236 : : static pgsocket *ListenSockets = NULL;
237 : :
238 : : /* still more option variables */
239 : : bool EnableSSL = false;
240 : :
241 : : int PreAuthDelay = 0;
242 : : int AuthenticationTimeout = 60;
243 : :
244 : : bool log_hostname; /* for ps display and logging */
245 : :
246 : : bool enable_bonjour = false;
247 : : char *bonjour_name;
248 : : bool restart_after_crash = true;
249 : : bool remove_temp_files_after_crash = true;
250 : :
251 : : /*
252 : : * When terminating child processes after fatal errors, like a crash of a
253 : : * child process, we normally send SIGQUIT -- and most other comments in this
254 : : * file are written on the assumption that we do -- but developers might
255 : : * prefer to use SIGABRT to collect per-child core dumps.
256 : : */
257 : : bool send_abort_for_crash = false;
258 : : bool send_abort_for_kill = false;
259 : :
260 : : /* special child processes; NULL when not running */
261 : : static PMChild *StartupPMChild = NULL,
262 : : *BgWriterPMChild = NULL,
263 : : *CheckpointerPMChild = NULL,
264 : : *WalWriterPMChild = NULL,
265 : : *WalReceiverPMChild = NULL,
266 : : *WalSummarizerPMChild = NULL,
267 : : *AutoVacLauncherPMChild = NULL,
268 : : *PgArchPMChild = NULL,
269 : : *SysLoggerPMChild = NULL,
270 : : *SlotSyncWorkerPMChild = NULL;
271 : :
272 : : /* Startup process's status */
273 : : typedef enum
274 : : {
275 : : STARTUP_NOT_RUNNING,
276 : : STARTUP_RUNNING,
277 : : STARTUP_SIGNALED, /* we sent it a SIGQUIT or SIGKILL */
278 : : STARTUP_CRASHED,
279 : : } StartupStatusEnum;
280 : :
281 : : static StartupStatusEnum StartupStatus = STARTUP_NOT_RUNNING;
282 : :
283 : : /* Startup/shutdown state */
284 : : #define NoShutdown 0
285 : : #define SmartShutdown 1
286 : : #define FastShutdown 2
287 : : #define ImmediateShutdown 3
288 : :
289 : : static int Shutdown = NoShutdown;
290 : :
291 : : static bool FatalError = false; /* T if recovering from backend crash */
292 : :
293 : : /*
294 : : * We use a simple state machine to control startup, shutdown, and
295 : : * crash recovery (which is rather like shutdown followed by startup).
296 : : *
297 : : * After doing all the postmaster initialization work, we enter PM_STARTUP
298 : : * state and the startup process is launched. The startup process begins by
299 : : * reading the control file and other preliminary initialization steps.
300 : : * In a normal startup, or after crash recovery, the startup process exits
301 : : * with exit code 0 and we switch to PM_RUN state. However, archive recovery
302 : : * is handled specially since it takes much longer and we would like to support
303 : : * hot standby during archive recovery.
304 : : *
305 : : * When the startup process is ready to start archive recovery, it signals the
306 : : * postmaster, and we switch to PM_RECOVERY state. The background writer and
307 : : * checkpointer are already running (as these are launched during PM_STARTUP),
308 : : * and the startup process continues applying WAL. If Hot Standby is enabled,
309 : : * then, after reaching a consistent point in WAL redo, startup process
310 : : * signals us again, and we switch to PM_HOT_STANDBY state and begin accepting
311 : : * connections to perform read-only queries. When archive recovery is
312 : : * finished, the startup process exits with exit code 0 and we switch to
313 : : * PM_RUN state.
314 : : *
315 : : * Normal child backends can only be launched when we are in PM_RUN or
316 : : * PM_HOT_STANDBY state. (connsAllowed can also restrict launching.)
317 : : * In other states we handle connection requests by launching "dead-end"
318 : : * child processes, which will simply send the client an error message and
319 : : * quit. (We track these in the ActiveChildList so that we can know when they
320 : : * are all gone; this is important because they're still connected to shared
321 : : * memory, and would interfere with an attempt to destroy the shmem segment,
322 : : * possibly leading to SHMALL failure when we try to make a new one.)
323 : : * In PM_WAIT_DEAD_END state we are waiting for all the dead-end children
324 : : * to drain out of the system, and therefore stop accepting connection
325 : : * requests at all until the last existing child has quit (which hopefully
326 : : * will not be very long).
327 : : *
328 : : * Notice that this state variable does not distinguish *why* we entered
329 : : * states later than PM_RUN --- Shutdown and FatalError must be consulted
330 : : * to find that out. FatalError is never true in PM_RECOVERY, PM_HOT_STANDBY,
331 : : * or PM_RUN states, nor in PM_WAIT_XLOG_SHUTDOWN states (because we don't
332 : : * enter those states when trying to recover from a crash). It can be true in
333 : : * PM_STARTUP state, because we don't clear it until we've successfully
334 : : * started WAL redo.
335 : : */
336 : : typedef enum
337 : : {
338 : : PM_INIT, /* postmaster starting */
339 : : PM_STARTUP, /* waiting for startup subprocess */
340 : : PM_RECOVERY, /* in archive recovery mode */
341 : : PM_HOT_STANDBY, /* in hot standby mode */
342 : : PM_RUN, /* normal "database is alive" state */
343 : : PM_STOP_BACKENDS, /* need to stop remaining backends */
344 : : PM_WAIT_BACKENDS, /* waiting for live backends to exit */
345 : : PM_WAIT_XLOG_SHUTDOWN, /* waiting for checkpointer to do shutdown
346 : : * ckpt */
347 : : PM_WAIT_XLOG_ARCHIVAL, /* waiting for archiver and walsenders to
348 : : * finish */
349 : : PM_WAIT_IO_WORKERS, /* waiting for io workers to exit */
350 : : PM_WAIT_CHECKPOINTER, /* waiting for checkpointer to shut down */
351 : : PM_WAIT_DEAD_END, /* waiting for dead-end children to exit */
352 : : PM_NO_CHILDREN, /* all important children have exited */
353 : : } PMState;
354 : :
355 : : static PMState pmState = PM_INIT;
356 : :
357 : : /*
358 : : * While performing a "smart shutdown", we restrict new connections but stay
359 : : * in PM_RUN or PM_HOT_STANDBY state until all the client backends are gone.
360 : : * connsAllowed is a sub-state indicator showing the active restriction.
361 : : * It is of no interest unless pmState is PM_RUN or PM_HOT_STANDBY.
362 : : */
363 : : static bool connsAllowed = true;
364 : :
365 : : /* Start time of SIGKILL timeout during immediate shutdown or child crash */
366 : : /* Zero means timeout is not running */
367 : : static time_t AbortStartTime = 0;
368 : :
369 : : /* Length of said timeout */
370 : : #define SIGKILL_CHILDREN_AFTER_SECS 5
371 : :
372 : : static bool ReachedNormalRunning = false; /* T if we've reached PM_RUN */
373 : :
374 : : bool ClientAuthInProgress = false; /* T during new-client
375 : : * authentication */
376 : :
377 : : bool redirection_done = false; /* stderr redirected for syslogger? */
378 : :
379 : : /* received START_AUTOVAC_LAUNCHER signal */
380 : : static bool start_autovac_launcher = false;
381 : :
382 : : /* the launcher needs to be signaled to communicate some condition */
383 : : static bool avlauncher_needs_signal = false;
384 : :
385 : : /* received START_WALRECEIVER signal */
386 : : static bool WalReceiverRequested = false;
387 : :
388 : : /* set when there's a worker that needs to be started up */
389 : : static bool StartWorkerNeeded = true;
390 : : static bool HaveCrashedWorker = false;
391 : :
392 : : /* set when signals arrive */
393 : : static volatile sig_atomic_t pending_pm_pmsignal;
394 : : static volatile sig_atomic_t pending_pm_child_exit;
395 : : static volatile sig_atomic_t pending_pm_reload_request;
396 : : static volatile sig_atomic_t pending_pm_shutdown_request;
397 : : static volatile sig_atomic_t pending_pm_fast_shutdown_request;
398 : : static volatile sig_atomic_t pending_pm_immediate_shutdown_request;
399 : :
400 : : /* event multiplexing object */
401 : : static WaitEventSet *pm_wait_set;
402 : :
403 : : #ifdef USE_SSL
404 : : /* Set when and if SSL has been initialized properly */
405 : : bool LoadedSSL = false;
406 : : #endif
407 : :
408 : : #ifdef USE_BONJOUR
409 : : static DNSServiceRef bonjour_sdref = NULL;
410 : : #endif
411 : :
412 : : /* State for IO worker management. */
413 : : static TimestampTz io_worker_launch_next_time = 0;
414 : : static int io_worker_count = 0;
415 : : static PMChild *io_worker_children[MAX_IO_WORKERS];
416 : :
417 : : /*
418 : : * postmaster.c - function prototypes
419 : : */
420 : : static void CloseServerPorts(int status, Datum arg);
421 : : static void unlink_external_pid_file(int status, Datum arg);
422 : : static void getInstallationPaths(const char *argv0);
423 : : static void checkControlFile(void);
424 : : static void handle_pm_pmsignal_signal(SIGNAL_ARGS);
425 : : static void handle_pm_child_exit_signal(SIGNAL_ARGS);
426 : : static void handle_pm_reload_request_signal(SIGNAL_ARGS);
427 : : static void handle_pm_shutdown_request_signal(SIGNAL_ARGS);
428 : : static void process_pm_pmsignal(void);
429 : : static void process_pm_child_exit(void);
430 : : static void process_pm_reload_request(void);
431 : : static void process_pm_shutdown_request(void);
432 : : static void dummy_handler(SIGNAL_ARGS);
433 : : static void CleanupBackend(PMChild *bp, int exitstatus);
434 : : static void HandleChildCrash(int pid, int exitstatus, const char *procname);
435 : : static void LogChildExit(int lev, const char *procname,
436 : : int pid, int exitstatus);
437 : : static void PostmasterStateMachine(void);
438 : : static void UpdatePMState(PMState newState);
439 : :
440 : : pg_noreturn static void ExitPostmaster(int status);
441 : : static int ServerLoop(void);
442 : : static int BackendStartup(ClientSocket *client_sock);
443 : : static void report_fork_failure_to_client(ClientSocket *client_sock, int errnum);
444 : : static CAC_state canAcceptConnections(BackendType backend_type);
445 : : static void signal_child(PMChild *pmchild, int signal);
446 : : static bool SignalChildren(int signal, BackendTypeMask targetMask);
447 : : static void TerminateChildren(int signal);
448 : : static int CountChildren(BackendTypeMask targetMask);
449 : : static void LaunchMissingBackgroundProcesses(void);
450 : : static void maybe_start_bgworkers(void);
451 : : static bool maybe_reap_io_worker(int pid);
452 : : static void maybe_start_io_workers(void);
453 : : static TimestampTz maybe_start_io_workers_scheduled_at(void);
454 : : static bool CreateOptsFile(int argc, char *argv[], char *fullprogname);
455 : : static PMChild *StartChildProcess(BackendType type);
456 : : static void StartSysLogger(void);
457 : : static void StartAutovacuumWorker(void);
458 : : static bool StartBackgroundWorker(RegisteredBgWorker *rw);
459 : : static void InitPostmasterDeathWatchHandle(void);
460 : :
461 : : #ifdef WIN32
462 : : #define WNOHANG 0 /* ignored, so any integer value will do */
463 : :
464 : : static pid_t waitpid(pid_t pid, int *exitstatus, int options);
465 : : static void WINAPI pgwin32_deadchild_callback(PVOID lpParameter, BOOLEAN TimerOrWaitFired);
466 : :
467 : : static HANDLE win32ChildQueue;
468 : :
469 : : typedef struct
470 : : {
471 : : HANDLE waitHandle;
472 : : HANDLE procHandle;
473 : : DWORD procId;
474 : : } win32_deadchild_waitinfo;
475 : : #endif /* WIN32 */
476 : :
477 : : /* Macros to check exit status of a child process */
478 : : #define EXIT_STATUS_0(st) ((st) == 0)
479 : : #define EXIT_STATUS_1(st) (WIFEXITED(st) && WEXITSTATUS(st) == 1)
480 : : #define EXIT_STATUS_3(st) (WIFEXITED(st) && WEXITSTATUS(st) == 3)
481 : :
482 : : #ifndef WIN32
483 : : /*
484 : : * File descriptors for pipe used to monitor if postmaster is alive.
485 : : * First is POSTMASTER_FD_WATCH, second is POSTMASTER_FD_OWN.
486 : : */
487 : : int postmaster_alive_fds[2] = {-1, -1};
488 : : #else
489 : : /* Process handle of postmaster used for the same purpose on Windows */
490 : : HANDLE PostmasterHandle;
491 : : #endif
492 : :
493 : : /*
494 : : * Postmaster main entry point
495 : : */
496 : : void
497 : 1025 : PostmasterMain(int argc, char *argv[])
498 : : {
499 : : pg_getopt_ctx optctx;
500 : : int opt;
501 : : int status;
502 : 1025 : char *userDoption = NULL;
503 : 1025 : bool listen_addr_saved = false;
504 : 1025 : char *output_config_variable = NULL;
505 : :
506 : 1025 : InitProcessGlobals();
507 : :
508 : 1025 : PostmasterPid = MyProcPid;
509 : :
510 : 1025 : IsPostmasterEnvironment = true;
511 : :
512 : : /*
513 : : * Start our win32 signal implementation
514 : : */
515 : : #ifdef WIN32
516 : : pgwin32_signal_initialize();
517 : : #endif
518 : :
519 : : /*
520 : : * We should not be creating any files or directories before we check the
521 : : * data directory (see checkDataDir()), but just in case set the umask to
522 : : * the most restrictive (owner-only) permissions.
523 : : *
524 : : * checkDataDir() will reset the umask based on the data directory
525 : : * permissions.
526 : : */
527 : 1025 : umask(PG_MODE_MASK_OWNER);
528 : :
529 : : /*
530 : : * By default, palloc() requests in the postmaster will be allocated in
531 : : * the PostmasterContext, which is space that can be recycled by backends.
532 : : * Allocated data that needs to be available to backends should be
533 : : * allocated in TopMemoryContext.
534 : : */
535 : 1025 : PostmasterContext = AllocSetContextCreate(TopMemoryContext,
536 : : "Postmaster",
537 : : ALLOCSET_DEFAULT_SIZES);
538 : 1025 : MemoryContextSwitchTo(PostmasterContext);
539 : :
540 : : /* Initialize paths to installation files */
541 : 1025 : getInstallationPaths(argv[0]);
542 : :
543 : : /*
544 : : * Set up signal handlers for the postmaster process.
545 : : *
546 : : * CAUTION: when changing this list, check for side-effects on the signal
547 : : * handling setup of child processes. See tcop/postgres.c,
548 : : * bootstrap/bootstrap.c, postmaster/bgwriter.c, postmaster/walwriter.c,
549 : : * postmaster/autovacuum.c, postmaster/pgarch.c, postmaster/syslogger.c,
550 : : * postmaster/bgworker.c and postmaster/checkpointer.c.
551 : : */
552 : 1025 : pqinitmask();
553 : 1025 : sigprocmask(SIG_SETMASK, &BlockSig, NULL);
554 : :
555 : 1025 : pqsignal(SIGHUP, handle_pm_reload_request_signal);
556 : 1025 : pqsignal(SIGINT, handle_pm_shutdown_request_signal);
557 : 1025 : pqsignal(SIGQUIT, handle_pm_shutdown_request_signal);
558 : 1025 : pqsignal(SIGTERM, handle_pm_shutdown_request_signal);
559 : 1025 : pqsignal(SIGALRM, PG_SIG_IGN); /* ignored */
560 : 1025 : pqsignal(SIGPIPE, PG_SIG_IGN); /* ignored */
561 : 1025 : pqsignal(SIGUSR1, handle_pm_pmsignal_signal);
562 : 1025 : pqsignal(SIGUSR2, dummy_handler); /* unused, reserve for children */
563 : 1025 : pqsignal(SIGCHLD, handle_pm_child_exit_signal);
564 : :
565 : : /* This may configure SIGURG, depending on platform. */
566 : 1025 : InitializeWaitEventSupport();
567 : 1025 : InitProcessLocalLatch();
568 : :
569 : : /*
570 : : * No other place in Postgres should touch SIGTTIN/SIGTTOU handling. We
571 : : * ignore those signals in a postmaster environment, so that there is no
572 : : * risk of a child process freezing up due to writing to stderr. But for
573 : : * a standalone backend, their default handling is reasonable. Hence, all
574 : : * child processes should just allow the inherited settings to stand.
575 : : */
576 : : #ifdef SIGTTIN
577 : 1025 : pqsignal(SIGTTIN, PG_SIG_IGN); /* ignored */
578 : : #endif
579 : : #ifdef SIGTTOU
580 : 1025 : pqsignal(SIGTTOU, PG_SIG_IGN); /* ignored */
581 : : #endif
582 : :
583 : : /* ignore SIGXFSZ, so that ulimit violations work like disk full */
584 : : #ifdef SIGXFSZ
585 : 1025 : pqsignal(SIGXFSZ, PG_SIG_IGN); /* ignored */
586 : : #endif
587 : :
588 : : /* Begin accepting signals. */
589 : 1025 : sigprocmask(SIG_SETMASK, &UnBlockSig, NULL);
590 : :
591 : : /*
592 : : * Options setup
593 : : */
594 : 1025 : InitializeGUCOptions();
595 : :
596 : : /*
597 : : * Parse command-line options. CAUTION: keep this in sync with
598 : : * tcop/postgres.c (the option sets should not conflict) and with the
599 : : * common help() function in main/main.c.
600 : : */
601 : 1025 : pg_getopt_start(&optctx, argc, argv, "B:bC:c:D:d:EeFf:h:ijk:lN:OPp:r:S:sTt:W:-:");
602 : 1025 : optctx.opterr = 1;
603 [ + + ]: 3665 : while ((opt = pg_getopt_next(&optctx)) != -1)
604 : : {
605 [ - + + + : 2644 : switch (opt)
+ + - - -
+ - - - -
+ - - - -
+ - - - -
- - - ]
606 : : {
607 : 0 : case 'B':
608 : 0 : SetConfigOption("shared_buffers", optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV);
609 : 0 : break;
610 : :
611 : 55 : case 'b':
612 : : /* Undocumented flag used for binary upgrades */
613 : 55 : IsBinaryUpgrade = true;
614 : 55 : break;
615 : :
616 : 5 : case 'C':
617 : 5 : output_config_variable = strdup(optctx.optarg);
618 : 5 : break;
619 : :
620 : 834 : case '-':
621 : :
622 : : /*
623 : : * Error if the user misplaced a special must-be-first option
624 : : * for dispatching to a subprogram. parse_dispatch_option()
625 : : * returns DISPATCH_POSTMASTER if it doesn't find a match, so
626 : : * error for anything else.
627 : : */
628 [ - + ]: 834 : if (parse_dispatch_option(optctx.optarg) != DISPATCH_POSTMASTER)
629 [ # # ]: 0 : ereport(ERROR,
630 : : (errcode(ERRCODE_SYNTAX_ERROR),
631 : : errmsg("--%s must be first argument", optctx.optarg)));
632 : :
633 : : pg_fallthrough;
634 : : case 'c':
635 : : {
636 : : char *name,
637 : : *value;
638 : :
639 : 1288 : ParseLongOption(optctx.optarg, &name, &value);
640 [ + + ]: 1288 : if (!value)
641 : : {
642 [ + - ]: 1 : if (opt == '-')
643 [ + - ]: 1 : ereport(ERROR,
644 : : (errcode(ERRCODE_SYNTAX_ERROR),
645 : : errmsg("--%s requires a value",
646 : : optctx.optarg)));
647 : : else
648 [ # # ]: 0 : ereport(ERROR,
649 : : (errcode(ERRCODE_SYNTAX_ERROR),
650 : : errmsg("-c %s requires a value",
651 : : optctx.optarg)));
652 : : }
653 : :
654 : 1287 : SetConfigOption(name, value, PGC_POSTMASTER, PGC_S_ARGV);
655 : 1284 : pfree(name);
656 : 1284 : pfree(value);
657 : 1284 : break;
658 : : }
659 : :
660 : 1021 : case 'D':
661 : 1021 : userDoption = strdup(optctx.optarg);
662 : 1021 : break;
663 : :
664 : 0 : case 'd':
665 : 0 : set_debug_options(atoi(optctx.optarg), PGC_POSTMASTER, PGC_S_ARGV);
666 : 0 : break;
667 : :
668 : 0 : case 'E':
669 : 0 : SetConfigOption("log_statement", "all", PGC_POSTMASTER, PGC_S_ARGV);
670 : 0 : break;
671 : :
672 : 0 : case 'e':
673 : 0 : SetConfigOption("datestyle", "euro", PGC_POSTMASTER, PGC_S_ARGV);
674 : 0 : break;
675 : :
676 : 104 : case 'F':
677 : 104 : SetConfigOption("fsync", "false", PGC_POSTMASTER, PGC_S_ARGV);
678 : 104 : break;
679 : :
680 : 0 : case 'f':
681 [ # # ]: 0 : if (!set_plan_disabling_options(optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV))
682 : : {
683 : 0 : write_stderr("%s: invalid argument for option -f: \"%s\"\n",
684 : : progname, optctx.optarg);
685 : 0 : ExitPostmaster(1);
686 : : }
687 : 0 : break;
688 : :
689 : 0 : case 'h':
690 : 0 : SetConfigOption("listen_addresses", optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV);
691 : 0 : break;
692 : :
693 : 0 : case 'i':
694 : 0 : SetConfigOption("listen_addresses", "*", PGC_POSTMASTER, PGC_S_ARGV);
695 : 0 : break;
696 : :
697 : 0 : case 'j':
698 : : /* only used by interactive backend */
699 : 0 : break;
700 : :
701 : 104 : case 'k':
702 : 104 : SetConfigOption("unix_socket_directories", optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV);
703 : 104 : break;
704 : :
705 : 0 : case 'l':
706 : 0 : SetConfigOption("ssl", "true", PGC_POSTMASTER, PGC_S_ARGV);
707 : 0 : break;
708 : :
709 : 0 : case 'N':
710 : 0 : SetConfigOption("max_connections", optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV);
711 : 0 : break;
712 : :
713 : 0 : case 'O':
714 : 0 : SetConfigOption("allow_system_table_mods", "true", PGC_POSTMASTER, PGC_S_ARGV);
715 : 0 : break;
716 : :
717 : 0 : case 'P':
718 : 0 : SetConfigOption("ignore_system_indexes", "true", PGC_POSTMASTER, PGC_S_ARGV);
719 : 0 : break;
720 : :
721 : 67 : case 'p':
722 : 67 : SetConfigOption("port", optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV);
723 : 67 : break;
724 : :
725 : 0 : case 'r':
726 : : /* only used by single-user backend */
727 : 0 : break;
728 : :
729 : 0 : case 'S':
730 : 0 : SetConfigOption("work_mem", optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV);
731 : 0 : break;
732 : :
733 : 0 : case 's':
734 : 0 : SetConfigOption("log_statement_stats", "true", PGC_POSTMASTER, PGC_S_ARGV);
735 : 0 : break;
736 : :
737 : 0 : case 'T':
738 : :
739 : : /*
740 : : * This option used to be defined as sending SIGSTOP after a
741 : : * backend crash, but sending SIGABRT seems more useful.
742 : : */
743 : 0 : SetConfigOption("send_abort_for_crash", "true", PGC_POSTMASTER, PGC_S_ARGV);
744 : 0 : break;
745 : :
746 : 0 : case 't':
747 : : {
748 : 0 : const char *tmp = get_stats_option_name(optctx.optarg);
749 : :
750 [ # # ]: 0 : if (tmp)
751 : : {
752 : 0 : SetConfigOption(tmp, "true", PGC_POSTMASTER, PGC_S_ARGV);
753 : : }
754 : : else
755 : : {
756 : 0 : write_stderr("%s: invalid argument for option -t: \"%s\"\n",
757 : : progname, optctx.optarg);
758 : 0 : ExitPostmaster(1);
759 : : }
760 : 0 : break;
761 : : }
762 : :
763 : 0 : case 'W':
764 : 0 : SetConfigOption("post_auth_delay", optctx.optarg, PGC_POSTMASTER, PGC_S_ARGV);
765 : 0 : break;
766 : :
767 : 0 : default:
768 : 0 : write_stderr("Try \"%s --help\" for more information.\n",
769 : : progname);
770 : 0 : ExitPostmaster(1);
771 : : }
772 : : }
773 : :
774 : : /*
775 : : * Postmaster accepts no non-option switch arguments.
776 : : */
777 [ - + ]: 1021 : if (optctx.optind < argc)
778 : : {
779 : 0 : write_stderr("%s: invalid argument: \"%s\"\n",
780 : 0 : progname, argv[optctx.optind]);
781 : 0 : write_stderr("Try \"%s --help\" for more information.\n",
782 : : progname);
783 : 0 : ExitPostmaster(1);
784 : : }
785 : :
786 : : /*
787 : : * Locate the proper configuration files and data directory, and read
788 : : * postgresql.conf for the first time.
789 : : */
790 [ - + ]: 1021 : if (!SelectConfigFiles(userDoption, progname))
791 : 0 : ExitPostmaster(2);
792 : :
793 [ + + ]: 1021 : if (output_config_variable != NULL)
794 : : {
795 : : /*
796 : : * If this is a runtime-computed GUC, it hasn't yet been initialized,
797 : : * and the present value is not useful. However, this is a convenient
798 : : * place to print the value for most GUCs because it is safe to run
799 : : * postmaster startup to this point even if the server is already
800 : : * running. For the handful of runtime-computed GUCs that we cannot
801 : : * provide meaningful values for yet, we wait until later in
802 : : * postmaster startup to print the value. We won't be able to use -C
803 : : * on running servers for those GUCs, but using this option now would
804 : : * lead to incorrect results for them.
805 : : */
806 : 2 : int flags = GetConfigOptionFlags(output_config_variable, true);
807 : :
808 [ + + ]: 2 : if ((flags & GUC_RUNTIME_COMPUTED) == 0)
809 : : {
810 : : /*
811 : : * "-C guc" was specified, so print GUC's value and exit. No
812 : : * extra permission check is needed because the user is reading
813 : : * inside the data dir.
814 : : */
815 : 1 : const char *config_val = GetConfigOption(output_config_variable,
816 : : false, false);
817 : :
818 [ + - ]: 1 : puts(config_val ? config_val : "");
819 : 1 : ExitPostmaster(0);
820 : : }
821 : :
822 : : /*
823 : : * A runtime-computed GUC will be printed later on. As we initialize
824 : : * a server startup sequence, silence any log messages that may show
825 : : * up in the output generated. FATAL and more severe messages are
826 : : * useful to show, even if one would only expect at least PANIC. LOG
827 : : * entries are hidden.
828 : : */
829 : 1 : SetConfigOption("log_min_messages", "FATAL", PGC_SUSET,
830 : : PGC_S_OVERRIDE);
831 : : }
832 : :
833 : : /* Verify that DataDir looks reasonable */
834 : 1020 : checkDataDir();
835 : :
836 : : /* Check that pg_control exists */
837 : 1020 : checkControlFile();
838 : :
839 : : /* And switch working directory into it */
840 : 1020 : ChangeToDataDir();
841 : :
842 : : /*
843 : : * Check for invalid combinations of GUC settings.
844 : : */
845 [ - + ]: 1020 : if (SuperuserReservedConnections + ReservedConnections >= MaxConnections)
846 : : {
847 : 0 : write_stderr("%s: \"superuser_reserved_connections\" (%d) plus \"reserved_connections\" (%d) must be less than \"max_connections\" (%d)\n",
848 : : progname,
849 : : SuperuserReservedConnections, ReservedConnections,
850 : : MaxConnections);
851 : 0 : ExitPostmaster(1);
852 : : }
853 [ + + - + ]: 1020 : if (XLogArchiveMode > ARCHIVE_MODE_OFF && wal_level == WAL_LEVEL_MINIMAL)
854 [ # # ]: 0 : ereport(ERROR,
855 : : (errmsg("WAL archival cannot be enabled when \"wal_level\" is \"minimal\"")));
856 [ + + - + ]: 1020 : if (max_wal_senders > 0 && wal_level == WAL_LEVEL_MINIMAL)
857 [ # # ]: 0 : ereport(ERROR,
858 : : (errmsg("WAL streaming (\"max_wal_senders\" > 0) requires \"wal_level\" to be \"replica\" or \"logical\"")));
859 [ + + - + ]: 1020 : if (summarize_wal && wal_level == WAL_LEVEL_MINIMAL)
860 [ # # ]: 0 : ereport(ERROR,
861 : : (errmsg("WAL cannot be summarized when \"wal_level\" is \"minimal\"")));
862 [ + + - + ]: 1020 : if (sync_replication_slots && wal_level == WAL_LEVEL_MINIMAL)
863 [ # # ]: 0 : ereport(ERROR,
864 : : (errmsg("replication slot synchronization (\"sync_replication_slots\" = on) requires \"wal_level\" to be \"replica\" or \"logical\"")));
865 : :
866 : : /*
867 : : * Other one-time internal sanity checks can go here, if they are fast.
868 : : * (Put any slow processing further down, after postmaster.pid creation.)
869 : : */
870 [ - + ]: 1020 : if (!CheckDateTokenTables())
871 : : {
872 : 0 : write_stderr("%s: invalid datetoken tables, please fix\n", progname);
873 : 0 : ExitPostmaster(1);
874 : : }
875 : :
876 : : /* For debugging: display postmaster environment */
877 [ + + ]: 1020 : if (message_level_is_interesting(DEBUG3))
878 : : {
879 : : #if !defined(WIN32)
880 : : extern char **environ;
881 : : #endif
882 : : char **p;
883 : : StringInfoData si;
884 : :
885 : 7 : initStringInfo(&si);
886 : :
887 : 7 : appendStringInfoString(&si, "initial environment dump:");
888 [ + + ]: 296 : for (p = environ; *p; ++p)
889 : 289 : appendStringInfo(&si, "\n%s", *p);
890 : :
891 [ + - ]: 7 : ereport(DEBUG3, errmsg_internal("%s", si.data));
892 : 7 : pfree(si.data);
893 : : }
894 : :
895 : : /*
896 : : * Create lockfile for data directory.
897 : : *
898 : : * We want to do this before we try to grab the input sockets, because the
899 : : * data directory interlock is more reliable than the socket-file
900 : : * interlock (thanks to whoever decided to put socket files in /tmp :-().
901 : : * For the same reason, it's best to grab the TCP socket(s) before the
902 : : * Unix socket(s).
903 : : *
904 : : * Also note that this internally sets up the on_proc_exit function that
905 : : * is responsible for removing both data directory and socket lockfiles;
906 : : * so it must happen before opening sockets so that at exit, the socket
907 : : * lockfiles go away after CloseServerPorts runs.
908 : : */
909 : 1020 : CreateDataDirLockFile(true);
910 : :
911 : : /*
912 : : * Read the control file (for error checking and config info).
913 : : *
914 : : * Since we verify the control file's CRC, this has a useful side effect
915 : : * on machines where we need a run-time test for CRC support instructions.
916 : : * The postmaster will do the test once at startup, and then its child
917 : : * processes will inherit the correct function pointer and not need to
918 : : * repeat the test.
919 : : */
920 : 1019 : LocalProcessControlFile(false);
921 : :
922 : : /*
923 : : * Register the apply launcher. It's probably a good idea to call this
924 : : * before any modules had a chance to take the background worker slots.
925 : : */
926 : 1019 : ApplyLauncherRegister();
927 : :
928 : : /*
929 : : * Register the shared memory needs of all core subsystems.
930 : : */
931 : 1019 : RegisterBuiltinShmemCallbacks();
932 : :
933 : : /*
934 : : * process any libraries that should be preloaded at postmaster start
935 : : */
936 : 1019 : process_shared_preload_libraries();
937 : :
938 : : /*
939 : : * Initialize SSL library, if specified.
940 : : */
941 : : #ifdef USE_SSL
942 [ + + ]: 1019 : if (EnableSSL)
943 : : {
944 : 51 : (void) secure_initialize(true);
945 : 38 : LoadedSSL = true;
946 : : }
947 : : #endif
948 : :
949 : : /*
950 : : * Now that loadable modules have had their chance to alter any GUCs,
951 : : * calculate MaxBackends and initialize the machinery to track child
952 : : * processes.
953 : : */
954 : 1006 : InitializeMaxBackends();
955 : 1006 : InitPostmasterChildSlots();
956 : :
957 : : /*
958 : : * Calculate the size of the PGPROC fast-path lock arrays.
959 : : */
960 : 1006 : InitializeFastPathLocks();
961 : :
962 : : /*
963 : : * Also call any legacy shmem request hooks that might've been installed
964 : : * by preloaded libraries.
965 : : *
966 : : * Note: this must be done before ShmemCallRequestCallbacks(), because the
967 : : * hooks may request LWLocks with RequestNamedLWLockTranche(), which in
968 : : * turn affects the size of the LWLock array calculated in lwlock.c.
969 : : */
970 : 1006 : process_shmem_requests();
971 : :
972 : : /*
973 : : * Ask all subsystems, including preloaded libraries, to register their
974 : : * shared memory needs.
975 : : */
976 : 1006 : ShmemCallRequestCallbacks();
977 : :
978 : : /*
979 : : * Now that loadable modules have had their chance to request additional
980 : : * shared memory, determine the value of any runtime-computed GUCs that
981 : : * depend on the amount of shared memory required.
982 : : */
983 : 1006 : InitializeShmemGUCs();
984 : :
985 : : /*
986 : : * Now that modules have been loaded, we can process any custom resource
987 : : * managers specified in the wal_consistency_checking GUC.
988 : : */
989 : 1006 : InitializeWalConsistencyChecking();
990 : :
991 : : /*
992 : : * If -C was specified with a runtime-computed GUC, we held off printing
993 : : * the value earlier, as the GUC was not yet initialized. We handle -C
994 : : * for most GUCs before we lock the data directory so that the option may
995 : : * be used on a running server. However, a handful of GUCs are runtime-
996 : : * computed and do not have meaningful values until after locking the data
997 : : * directory, and we cannot safely calculate their values earlier on a
998 : : * running server. At this point, such GUCs should be properly
999 : : * initialized, and we haven't yet set up shared memory, so this is a good
1000 : : * time to handle the -C option for these special GUCs.
1001 : : */
1002 [ + + ]: 1006 : if (output_config_variable != NULL)
1003 : : {
1004 : 1 : const char *config_val = GetConfigOption(output_config_variable,
1005 : : false, false);
1006 : :
1007 [ + - ]: 1 : puts(config_val ? config_val : "");
1008 : 1 : ExitPostmaster(0);
1009 : : }
1010 : :
1011 : : /*
1012 : : * Set up shared memory and semaphores.
1013 : : *
1014 : : * Note: if using SysV shmem and/or semas, each postmaster startup will
1015 : : * normally choose the same IPC keys. This helps ensure that we will
1016 : : * clean up dead IPC objects if the postmaster crashes and is restarted.
1017 : : */
1018 : 1005 : CreateSharedMemoryAndSemaphores();
1019 : :
1020 : : /*
1021 : : * Estimate number of openable files. This must happen after setting up
1022 : : * semaphores, because on some platforms semaphores count as open files.
1023 : : */
1024 : 1004 : set_max_safe_fds();
1025 : :
1026 : : /*
1027 : : * Initialize pipe (or process handle on Windows) that allows children to
1028 : : * wake up from sleep on postmaster death.
1029 : : */
1030 : 1004 : InitPostmasterDeathWatchHandle();
1031 : :
1032 : : #ifdef WIN32
1033 : :
1034 : : /*
1035 : : * Initialize I/O completion port used to deliver list of dead children.
1036 : : */
1037 : : win32ChildQueue = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 1);
1038 : : if (win32ChildQueue == NULL)
1039 : : ereport(FATAL,
1040 : : (errmsg("could not create I/O completion port for child queue")));
1041 : : #endif
1042 : :
1043 : : #ifdef EXEC_BACKEND
1044 : : /* Write out nondefault GUC settings for child processes to use */
1045 : : write_nondefault_variables(PGC_POSTMASTER);
1046 : :
1047 : : /*
1048 : : * Clean out the temp directory used to transmit parameters to child
1049 : : * processes (see internal_forkexec). We must do this before launching
1050 : : * any child processes, else we have a race condition: we could remove a
1051 : : * parameter file before the child can read it. It should be safe to do
1052 : : * so now, because we verified earlier that there are no conflicting
1053 : : * Postgres processes in this data directory.
1054 : : */
1055 : : RemovePgTempFilesInDir(PG_TEMP_FILES_DIR, true, false);
1056 : : #endif
1057 : :
1058 : : /*
1059 : : * Forcibly remove the files signaling a standby promotion request.
1060 : : * Otherwise, the existence of those files triggers a promotion too early,
1061 : : * whether a user wants that or not.
1062 : : *
1063 : : * This removal of files is usually unnecessary because they can exist
1064 : : * only during a few moments during a standby promotion. However there is
1065 : : * a race condition: if pg_ctl promote is executed and creates the files
1066 : : * during a promotion, the files can stay around even after the server is
1067 : : * brought up to be the primary. Then, if a new standby starts by using
1068 : : * the backup taken from the new primary, the files can exist at server
1069 : : * startup and must be removed in order to avoid an unexpected promotion.
1070 : : *
1071 : : * Note that promotion signal files need to be removed before the startup
1072 : : * process is invoked. Because, after that, they can be used by
1073 : : * postmaster's SIGUSR1 signal handler.
1074 : : */
1075 : 1004 : RemovePromoteSignalFiles();
1076 : :
1077 : : /* Do the same for logrotate signal file */
1078 : 1004 : RemoveLogrotateSignalFiles();
1079 : :
1080 : : /* Remove any outdated file holding the current log filenames. */
1081 [ + - - + ]: 1004 : if (unlink(LOG_METAINFO_DATAFILE) < 0 && errno != ENOENT)
1082 [ # # ]: 0 : ereport(LOG,
1083 : : (errcode_for_file_access(),
1084 : : errmsg("could not remove file \"%s\": %m",
1085 : : LOG_METAINFO_DATAFILE)));
1086 : :
1087 : : /*
1088 : : * If enabled, start up syslogger collection subprocess
1089 : : */
1090 [ + + ]: 1004 : if (Logging_collector)
1091 : 1 : StartSysLogger();
1092 : :
1093 : : /*
1094 : : * Reset whereToSendOutput from DestDebug (its starting state) to
1095 : : * DestNone. This stops ereport from sending log messages to stderr unless
1096 : : * Log_destination permits. We don't do this until the postmaster is
1097 : : * fully launched, since startup failures may as well be reported to
1098 : : * stderr.
1099 : : *
1100 : : * If we are in fact disabling logging to stderr, first emit a log message
1101 : : * saying so, to provide a breadcrumb trail for users who may not remember
1102 : : * that their logging is configured to go somewhere else.
1103 : : */
1104 [ - + ]: 1004 : if (!(Log_destination & LOG_DESTINATION_STDERR))
1105 [ # # ]: 0 : ereport(LOG,
1106 : : (errmsg("ending log output to stderr"),
1107 : : errhint("Future log output will go to log destination \"%s\".",
1108 : : Log_destination_string)));
1109 : :
1110 : 1004 : whereToSendOutput = DestNone;
1111 : :
1112 : : /*
1113 : : * Report server startup in log. While we could emit this much earlier,
1114 : : * it seems best to do so after starting the log collector, if we intend
1115 : : * to use one.
1116 : : */
1117 [ + - ]: 1004 : ereport(LOG,
1118 : : (errmsg("starting %s", PG_VERSION_STR)));
1119 : :
1120 : : /*
1121 : : * Establish input sockets.
1122 : : *
1123 : : * First set up an on_proc_exit function that's charged with closing the
1124 : : * sockets again at postmaster shutdown.
1125 : : */
1126 : 1004 : ListenSockets = palloc(MAXLISTEN * sizeof(pgsocket));
1127 : 1004 : on_proc_exit(CloseServerPorts, 0);
1128 : :
1129 [ + - ]: 1004 : if (ListenAddresses)
1130 : : {
1131 : : char *rawstring;
1132 : : List *elemlist;
1133 : : ListCell *l;
1134 : 1004 : int success = 0;
1135 : :
1136 : : /* Need a modifiable copy of ListenAddresses */
1137 : 1004 : rawstring = pstrdup(ListenAddresses);
1138 : :
1139 : : /* Parse string into list of hostnames */
1140 [ - + ]: 1004 : if (!SplitGUCList(rawstring, ',', &elemlist))
1141 : : {
1142 : : /* syntax error in list */
1143 [ # # ]: 0 : ereport(FATAL,
1144 : : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1145 : : errmsg("invalid list syntax in parameter \"%s\"",
1146 : : "listen_addresses")));
1147 : : }
1148 : :
1149 [ + + + + : 1045 : foreach(l, elemlist)
+ + ]
1150 : : {
1151 : 41 : char *curhost = (char *) lfirst(l);
1152 : :
1153 [ - + ]: 41 : if (strcmp(curhost, "*") == 0)
1154 : 0 : status = ListenServerPort(AF_UNSPEC, NULL,
1155 : 0 : (unsigned short) PostPortNumber,
1156 : : NULL,
1157 : : ListenSockets,
1158 : : &NumListenSockets,
1159 : : MAXLISTEN);
1160 : : else
1161 : 41 : status = ListenServerPort(AF_UNSPEC, curhost,
1162 : 41 : (unsigned short) PostPortNumber,
1163 : : NULL,
1164 : : ListenSockets,
1165 : : &NumListenSockets,
1166 : : MAXLISTEN);
1167 : :
1168 [ + - ]: 41 : if (status == STATUS_OK)
1169 : : {
1170 : 41 : success++;
1171 : : /* record the first successful host addr in lockfile */
1172 [ + - ]: 41 : if (!listen_addr_saved)
1173 : : {
1174 : 41 : AddToDataDirLockFile(LOCK_FILE_LINE_LISTEN_ADDR, curhost);
1175 : 41 : listen_addr_saved = true;
1176 : : }
1177 : : }
1178 : : else
1179 [ # # ]: 0 : ereport(WARNING,
1180 : : (errmsg("could not create listen socket for \"%s\"",
1181 : : curhost)));
1182 : : }
1183 : :
1184 [ + + - + ]: 1004 : if (!success && elemlist != NIL)
1185 [ # # ]: 0 : ereport(FATAL,
1186 : : (errmsg("could not create any TCP/IP sockets")));
1187 : :
1188 : 1004 : list_free(elemlist);
1189 : 1004 : pfree(rawstring);
1190 : : }
1191 : :
1192 : : #ifdef USE_BONJOUR
1193 : : /* Register for Bonjour only if we opened TCP socket(s) */
1194 : : if (enable_bonjour && NumListenSockets > 0)
1195 : : {
1196 : : DNSServiceErrorType err;
1197 : :
1198 : : /*
1199 : : * We pass 0 for interface_index, which will result in registering on
1200 : : * all "applicable" interfaces. It's not entirely clear from the
1201 : : * DNS-SD docs whether this would be appropriate if we have bound to
1202 : : * just a subset of the available network interfaces.
1203 : : */
1204 : : err = DNSServiceRegister(&bonjour_sdref,
1205 : : 0,
1206 : : 0,
1207 : : bonjour_name,
1208 : : "_postgresql._tcp.",
1209 : : NULL,
1210 : : NULL,
1211 : : pg_hton16(PostPortNumber),
1212 : : 0,
1213 : : NULL,
1214 : : NULL,
1215 : : NULL);
1216 : : if (err != kDNSServiceErr_NoError)
1217 : : ereport(LOG,
1218 : : (errmsg("DNSServiceRegister() failed: error code %ld",
1219 : : (long) err)));
1220 : :
1221 : : /*
1222 : : * We don't bother to read the mDNS daemon's reply, and we expect that
1223 : : * it will automatically terminate our registration when the socket is
1224 : : * closed at postmaster termination. So there's nothing more to be
1225 : : * done here. However, the bonjour_sdref is kept around so that
1226 : : * forked children can close their copies of the socket.
1227 : : */
1228 : : }
1229 : : #endif
1230 : :
1231 [ + - ]: 1004 : if (Unix_socket_directories)
1232 : : {
1233 : : char *rawstring;
1234 : : List *elemlist;
1235 : : ListCell *l;
1236 : 1004 : int success = 0;
1237 : :
1238 : : /* Need a modifiable copy of Unix_socket_directories */
1239 : 1004 : rawstring = pstrdup(Unix_socket_directories);
1240 : :
1241 : : /* Parse string into list of directories */
1242 [ - + ]: 1004 : if (!SplitDirectoriesString(rawstring, ',', &elemlist))
1243 : : {
1244 : : /* syntax error in list */
1245 [ # # ]: 0 : ereport(FATAL,
1246 : : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1247 : : errmsg("invalid list syntax in parameter \"%s\"",
1248 : : "unix_socket_directories")));
1249 : : }
1250 : :
1251 [ + + + + : 2007 : foreach(l, elemlist)
+ + ]
1252 : : {
1253 : 1003 : char *socketdir = (char *) lfirst(l);
1254 : :
1255 : 1003 : status = ListenServerPort(AF_UNIX, NULL,
1256 : 1003 : (unsigned short) PostPortNumber,
1257 : : socketdir,
1258 : : ListenSockets,
1259 : : &NumListenSockets,
1260 : : MAXLISTEN);
1261 : :
1262 [ + - ]: 1003 : if (status == STATUS_OK)
1263 : : {
1264 : 1003 : success++;
1265 : : /* record the first successful Unix socket in lockfile */
1266 [ + - ]: 1003 : if (success == 1)
1267 : 1003 : AddToDataDirLockFile(LOCK_FILE_LINE_SOCKET_DIR, socketdir);
1268 : : }
1269 : : else
1270 [ # # ]: 0 : ereport(WARNING,
1271 : : (errmsg("could not create Unix-domain socket in directory \"%s\"",
1272 : : socketdir)));
1273 : : }
1274 : :
1275 [ + + - + ]: 1004 : if (!success && elemlist != NIL)
1276 [ # # ]: 0 : ereport(FATAL,
1277 : : (errmsg("could not create any Unix-domain sockets")));
1278 : :
1279 : 1004 : list_free_deep(elemlist);
1280 : 1004 : pfree(rawstring);
1281 : : }
1282 : :
1283 : : /*
1284 : : * check that we have some socket to listen on
1285 : : */
1286 [ - + ]: 1004 : if (NumListenSockets == 0)
1287 [ # # ]: 0 : ereport(FATAL,
1288 : : (errmsg("no socket created for listening")));
1289 : :
1290 : : /*
1291 : : * If no valid TCP ports, write an empty line for listen address,
1292 : : * indicating the Unix socket must be used. Note that this line is not
1293 : : * added to the lock file until there is a socket backing it.
1294 : : */
1295 [ + + ]: 1004 : if (!listen_addr_saved)
1296 : 963 : AddToDataDirLockFile(LOCK_FILE_LINE_LISTEN_ADDR, "");
1297 : :
1298 : : /*
1299 : : * Record postmaster options. We delay this till now to avoid recording
1300 : : * bogus options (eg, unusable port number).
1301 : : */
1302 [ - + ]: 1004 : if (!CreateOptsFile(argc, argv, my_exec_path))
1303 : 0 : ExitPostmaster(1);
1304 : :
1305 : : /*
1306 : : * Write the external PID file if requested
1307 : : */
1308 [ - + ]: 1004 : if (external_pid_file)
1309 : : {
1310 : 0 : FILE *fpidfile = fopen(external_pid_file, "w");
1311 : :
1312 [ # # ]: 0 : if (fpidfile)
1313 : : {
1314 : 0 : fprintf(fpidfile, "%d\n", MyProcPid);
1315 : 0 : fclose(fpidfile);
1316 : :
1317 : : /* Make PID file world readable */
1318 [ # # ]: 0 : if (chmod(external_pid_file, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) != 0)
1319 : 0 : write_stderr("%s: could not change permissions of external PID file \"%s\": %m\n",
1320 : : progname, external_pid_file);
1321 : : }
1322 : : else
1323 : 0 : write_stderr("%s: could not write external PID file \"%s\": %m\n",
1324 : : progname, external_pid_file);
1325 : :
1326 : 0 : on_proc_exit(unlink_external_pid_file, 0);
1327 : : }
1328 : :
1329 : : /*
1330 : : * Remove old temporary files. At this point there can be no other
1331 : : * Postgres processes running in this directory, so this should be safe.
1332 : : */
1333 : 1004 : RemovePgTempFiles();
1334 : :
1335 : : /*
1336 : : * Initialize the autovacuum subsystem (again, no process start yet)
1337 : : */
1338 : 1004 : autovac_init();
1339 : :
1340 : : /*
1341 : : * Load configuration files for client authentication.
1342 : : */
1343 [ - + ]: 1004 : if (!load_hba())
1344 : : {
1345 : : /*
1346 : : * It makes no sense to continue if we fail to load the HBA file,
1347 : : * since there is no way to connect to the database in this case.
1348 : : */
1349 [ # # ]: 0 : ereport(FATAL,
1350 : : /* translator: %s is a configuration file */
1351 : : (errmsg("could not load %s", HbaFileName)));
1352 : : }
1353 : 1004 : if (!load_ident())
1354 : : {
1355 : : /*
1356 : : * We can start up without the IDENT file, although it means that you
1357 : : * cannot log in using any of the authentication methods that need a
1358 : : * user name mapping. load_ident() already logged the details of error
1359 : : * to the log.
1360 : : */
1361 : : }
1362 : :
1363 : : #ifdef HAVE_PTHREAD_IS_THREADED_NP
1364 : :
1365 : : /*
1366 : : * On macOS, libintl replaces setlocale() with a version that calls
1367 : : * CFLocaleCopyCurrent() when its second argument is "" and every relevant
1368 : : * environment variable is unset or empty. CFLocaleCopyCurrent() makes
1369 : : * the process multithreaded. The postmaster calls sigprocmask() and
1370 : : * calls fork() without an immediate exec(), both of which have undefined
1371 : : * behavior in a multithreaded program. A multithreaded postmaster is the
1372 : : * normal case on Windows, which offers neither fork() nor sigprocmask().
1373 : : * Currently, macOS is the only platform having pthread_is_threaded_np(),
1374 : : * so we need not worry whether this HINT is appropriate elsewhere.
1375 : : */
1376 : : if (pthread_is_threaded_np() != 0)
1377 : : ereport(FATAL,
1378 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
1379 : : errmsg("postmaster became multithreaded during startup"),
1380 : : errhint("Set the LC_ALL environment variable to a valid locale.")));
1381 : : #endif
1382 : :
1383 : : /*
1384 : : * Remember postmaster startup time
1385 : : */
1386 : 1004 : PgStartTime = GetCurrentTimestamp();
1387 : :
1388 : : /*
1389 : : * Report postmaster status in the postmaster.pid file, to allow pg_ctl to
1390 : : * see what's happening.
1391 : : */
1392 : 1004 : AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_STARTING);
1393 : :
1394 : 1004 : UpdatePMState(PM_STARTUP);
1395 : :
1396 : : /* Make sure we can perform I/O while starting up. */
1397 : 1004 : maybe_start_io_workers();
1398 : :
1399 : : /* Start bgwriter and checkpointer so they can help with recovery */
1400 [ + - ]: 1004 : if (CheckpointerPMChild == NULL)
1401 : 1004 : CheckpointerPMChild = StartChildProcess(B_CHECKPOINTER);
1402 [ + - ]: 1004 : if (BgWriterPMChild == NULL)
1403 : 1004 : BgWriterPMChild = StartChildProcess(B_BG_WRITER);
1404 : :
1405 : : /*
1406 : : * We're ready to rock and roll...
1407 : : */
1408 : 1004 : StartupPMChild = StartChildProcess(B_STARTUP);
1409 : : Assert(StartupPMChild != NULL);
1410 : 1004 : StartupStatus = STARTUP_RUNNING;
1411 : :
1412 : : /* Some workers may be scheduled to start now */
1413 : 1004 : maybe_start_bgworkers();
1414 : :
1415 : 1004 : status = ServerLoop();
1416 : :
1417 : : /*
1418 : : * ServerLoop probably shouldn't ever return, but if it does, close down.
1419 : : */
1420 : 0 : ExitPostmaster(status != STATUS_OK);
1421 : :
1422 : : abort(); /* not reached */
1423 : : }
1424 : :
1425 : :
1426 : : /*
1427 : : * on_proc_exit callback to close server's listen sockets
1428 : : */
1429 : : static void
1430 : 1004 : CloseServerPorts(int status, Datum arg)
1431 : : {
1432 : : int i;
1433 : :
1434 : : /*
1435 : : * First, explicitly close all the socket FDs. We used to just let this
1436 : : * happen implicitly at postmaster exit, but it's better to close them
1437 : : * before we remove the postmaster.pid lockfile; otherwise there's a race
1438 : : * condition if a new postmaster wants to re-use the TCP port number.
1439 : : */
1440 [ + + ]: 2049 : for (i = 0; i < NumListenSockets; i++)
1441 : : {
1442 [ - + ]: 1045 : if (closesocket(ListenSockets[i]) != 0)
1443 [ # # ]: 0 : elog(LOG, "could not close listen socket: %m");
1444 : : }
1445 : 1004 : NumListenSockets = 0;
1446 : :
1447 : : /*
1448 : : * Next, remove any filesystem entries for Unix sockets. To avoid race
1449 : : * conditions against incoming postmasters, this must happen after closing
1450 : : * the sockets and before removing lock files.
1451 : : */
1452 : 1004 : RemoveSocketFiles();
1453 : :
1454 : : /*
1455 : : * We don't do anything about socket lock files here; those will be
1456 : : * removed in a later on_proc_exit callback.
1457 : : */
1458 : 1004 : }
1459 : :
1460 : : /*
1461 : : * on_proc_exit callback to delete external_pid_file
1462 : : */
1463 : : static void
1464 : 0 : unlink_external_pid_file(int status, Datum arg)
1465 : : {
1466 [ # # ]: 0 : if (external_pid_file)
1467 : 0 : unlink(external_pid_file);
1468 : 0 : }
1469 : :
1470 : :
1471 : : /*
1472 : : * Compute and check the directory paths to files that are part of the
1473 : : * installation (as deduced from the postgres executable's own location)
1474 : : */
1475 : : static void
1476 : 1025 : getInstallationPaths(const char *argv0)
1477 : : {
1478 : : DIR *pdir;
1479 : :
1480 : : /* Locate the postgres executable itself */
1481 [ - + ]: 1025 : if (find_my_exec(argv0, my_exec_path) < 0)
1482 [ # # ]: 0 : ereport(FATAL,
1483 : : (errmsg("%s: could not locate my own executable path", argv0)));
1484 : :
1485 : : #ifdef EXEC_BACKEND
1486 : : /* Locate executable backend before we change working directory */
1487 : : if (find_other_exec(argv0, "postgres", PG_BACKEND_VERSIONSTR,
1488 : : postgres_exec_path) < 0)
1489 : : ereport(FATAL,
1490 : : (errmsg("%s: could not locate matching postgres executable",
1491 : : argv0)));
1492 : : #endif
1493 : :
1494 : : /*
1495 : : * Locate the pkglib directory --- this has to be set early in case we try
1496 : : * to load any modules from it in response to postgresql.conf entries.
1497 : : */
1498 : 1025 : get_pkglib_path(my_exec_path, pkglib_path);
1499 : :
1500 : : /*
1501 : : * Verify that there's a readable directory there; otherwise the Postgres
1502 : : * installation is incomplete or corrupt. (A typical cause of this
1503 : : * failure is that the postgres executable has been moved or hardlinked to
1504 : : * some directory that's not a sibling of the installation lib/
1505 : : * directory.)
1506 : : */
1507 : 1025 : pdir = AllocateDir(pkglib_path);
1508 [ - + ]: 1025 : if (pdir == NULL)
1509 [ # # ]: 0 : ereport(ERROR,
1510 : : (errcode_for_file_access(),
1511 : : errmsg("could not open directory \"%s\": %m",
1512 : : pkglib_path),
1513 : : errhint("This may indicate an incomplete PostgreSQL installation, or that the file \"%s\" has been moved away from its proper location.",
1514 : : my_exec_path)));
1515 : 1025 : FreeDir(pdir);
1516 : :
1517 : : /*
1518 : : * It's not worth checking the share/ directory. If the lib/ directory is
1519 : : * there, then share/ probably is too.
1520 : : */
1521 : 1025 : }
1522 : :
1523 : : /*
1524 : : * Check that pg_control exists in the correct location in the data directory.
1525 : : *
1526 : : * No attempt is made to validate the contents of pg_control here. This is
1527 : : * just a sanity check to see if we are looking at a real data directory.
1528 : : */
1529 : : static void
1530 : 1020 : checkControlFile(void)
1531 : : {
1532 : : char path[MAXPGPATH];
1533 : : FILE *fp;
1534 : :
1535 : 1020 : snprintf(path, sizeof(path), "%s/%s", DataDir, XLOG_CONTROL_FILE);
1536 : :
1537 : 1020 : fp = AllocateFile(path, PG_BINARY_R);
1538 [ - + ]: 1020 : if (fp == NULL)
1539 : : {
1540 : 0 : write_stderr("%s: could not find the database system\n"
1541 : : "Expected to find it in the directory \"%s\",\n"
1542 : : "but could not open file \"%s\": %m\n",
1543 : : progname, DataDir, path);
1544 : 0 : ExitPostmaster(2);
1545 : : }
1546 : 1020 : FreeFile(fp);
1547 : 1020 : }
1548 : :
1549 : : /*
1550 : : * Determine how long should we let ServerLoop sleep, in milliseconds.
1551 : : *
1552 : : * In normal conditions we wait at most one minute, to ensure that the other
1553 : : * background tasks handled by ServerLoop get done even when no requests are
1554 : : * arriving. However, if there are background workers waiting to be started,
1555 : : * we don't actually sleep so that they are quickly serviced. Other exception
1556 : : * cases are as shown in the code.
1557 : : */
1558 : : static int
1559 : 156322 : DetermineSleepTime(void)
1560 : : {
1561 : : TimestampTz next_wakeup;
1562 : :
1563 : : /*
1564 : : * If in ImmediateShutdown with a SIGKILL timeout, ignore everything else
1565 : : * and wait for that.
1566 : : *
1567 : : * XXX Shouldn't this also test FatalError?
1568 : : */
1569 [ + + ]: 156322 : if (Shutdown >= ImmediateShutdown)
1570 : : {
1571 [ + - ]: 1611 : if (AbortStartTime != 0)
1572 : : {
1573 : 1611 : time_t curtime = time(NULL);
1574 : : int seconds;
1575 : :
1576 : : /*
1577 : : * time left to abort; clamp to 0 if it already expired, or if
1578 : : * time goes backwards
1579 : : */
1580 [ + - ]: 1611 : if (curtime < AbortStartTime ||
1581 [ - + ]: 1611 : curtime - AbortStartTime >= SIGKILL_CHILDREN_AFTER_SECS)
1582 : 0 : seconds = 0;
1583 : : else
1584 : 1611 : seconds = SIGKILL_CHILDREN_AFTER_SECS -
1585 : : (curtime - AbortStartTime);
1586 : :
1587 : 1611 : return seconds * 1000;
1588 : : }
1589 : : }
1590 : :
1591 : : /* Time of next maybe_start_io_workers() call, or 0 for none. */
1592 : 154711 : next_wakeup = maybe_start_io_workers_scheduled_at();
1593 : :
1594 : : /* Ignore bgworkers during shutdown. */
1595 [ - + - - ]: 154711 : if (StartWorkerNeeded && Shutdown == NoShutdown)
1596 : 0 : return 0;
1597 : :
1598 [ + + - + ]: 154711 : if (HaveCrashedWorker && Shutdown == NoShutdown)
1599 : : {
1600 : : dlist_mutable_iter iter;
1601 : :
1602 : : /*
1603 : : * When there are crashed bgworkers, we sleep just long enough that
1604 : : * they are restarted when they request to be. Scan the list to
1605 : : * determine the minimum of all wakeup times according to most recent
1606 : : * crash time and requested restart interval.
1607 : : */
1608 [ # # # # ]: 0 : dlist_foreach_modify(iter, &BackgroundWorkerList)
1609 : : {
1610 : : RegisteredBgWorker *rw;
1611 : : TimestampTz this_wakeup;
1612 : :
1613 : 0 : rw = dlist_container(RegisteredBgWorker, rw_lnode, iter.cur);
1614 : :
1615 [ # # ]: 0 : if (rw->rw_crashed_at == 0)
1616 : 0 : continue;
1617 : :
1618 [ # # ]: 0 : if (rw->rw_worker.bgw_restart_time == BGW_NEVER_RESTART
1619 [ # # ]: 0 : || rw->rw_terminate)
1620 : : {
1621 : 0 : ForgetBackgroundWorker(rw);
1622 : 0 : continue;
1623 : : }
1624 : :
1625 : 0 : this_wakeup = TimestampTzPlusMilliseconds(rw->rw_crashed_at,
1626 : : 1000L * rw->rw_worker.bgw_restart_time);
1627 [ # # # # ]: 0 : if (next_wakeup == 0 || this_wakeup < next_wakeup)
1628 : 0 : next_wakeup = this_wakeup;
1629 : : }
1630 : : }
1631 : :
1632 [ + + ]: 154711 : if (next_wakeup != 0)
1633 : : {
1634 : : int ms;
1635 : :
1636 : : /* result of TimestampDifferenceMilliseconds is in [0, INT_MAX] */
1637 : 24 : ms = (int) TimestampDifferenceMilliseconds(GetCurrentTimestamp(),
1638 : : next_wakeup);
1639 : 24 : return Min(60 * 1000, ms);
1640 : : }
1641 : :
1642 : 154687 : return 60 * 1000;
1643 : : }
1644 : :
1645 : : /*
1646 : : * Activate or deactivate notifications of server socket events. Since we
1647 : : * don't currently have a way to remove events from an existing WaitEventSet,
1648 : : * we'll just destroy and recreate the whole thing. This is called during
1649 : : * shutdown so we can wait for backends to exit without accepting new
1650 : : * connections, and during crash reinitialization when we need to start
1651 : : * listening for new connections again. The WaitEventSet will be freed in fork
1652 : : * children by ClosePostmasterPorts().
1653 : : */
1654 : : static void
1655 : 2018 : ConfigurePostmasterWaitSet(bool accept_connections)
1656 : : {
1657 [ + + ]: 2018 : if (pm_wait_set)
1658 : 1014 : FreeWaitEventSet(pm_wait_set);
1659 : 2018 : pm_wait_set = NULL;
1660 : :
1661 : 4036 : pm_wait_set = CreateWaitEventSet(NULL,
1662 : 2018 : accept_connections ? (1 + NumListenSockets) : 1);
1663 : 2018 : AddWaitEventToSet(pm_wait_set, WL_LATCH_SET, PGINVALID_SOCKET, MyLatch,
1664 : : NULL);
1665 : :
1666 [ + + ]: 2018 : if (accept_connections)
1667 : : {
1668 [ + + ]: 2059 : for (int i = 0; i < NumListenSockets; i++)
1669 : 1050 : AddWaitEventToSet(pm_wait_set, WL_SOCKET_ACCEPT, ListenSockets[i],
1670 : : NULL, NULL);
1671 : : }
1672 : 2018 : }
1673 : :
1674 : : /*
1675 : : * Main idle loop of postmaster
1676 : : */
1677 : : static int
1678 : 1004 : ServerLoop(void)
1679 : : {
1680 : : time_t last_lockfile_recheck_time,
1681 : : last_touch_time;
1682 : : WaitEvent events[MAXLISTEN];
1683 : : int nevents;
1684 : :
1685 : 1004 : ConfigurePostmasterWaitSet(true);
1686 : 1004 : last_lockfile_recheck_time = last_touch_time = time(NULL);
1687 : :
1688 : : for (;;)
1689 : 155318 : {
1690 : : time_t now;
1691 : :
1692 : 156322 : nevents = WaitEventSetWait(pm_wait_set,
1693 : 156322 : DetermineSleepTime(),
1694 : : events,
1695 : : lengthof(events),
1696 : : 0 /* postmaster posts no wait_events */ );
1697 : :
1698 : : /*
1699 : : * Latch set by signal handler, or new connection pending on any of
1700 : : * our sockets? If the latter, fork a child process to deal with it.
1701 : : */
1702 [ + + ]: 311644 : for (int i = 0; i < nevents; i++)
1703 : : {
1704 [ + + ]: 156326 : if (events[i].events & WL_LATCH_SET)
1705 : 140907 : ResetLatch(MyLatch);
1706 : :
1707 : : /*
1708 : : * The following requests are handled unconditionally, even if we
1709 : : * didn't see WL_LATCH_SET. This gives high priority to shutdown
1710 : : * and reload requests where the latch happens to appear later in
1711 : : * events[] or will be reported by a later call to
1712 : : * WaitEventSetWait().
1713 : : */
1714 [ + + ]: 156326 : if (pending_pm_shutdown_request)
1715 : 993 : process_pm_shutdown_request();
1716 [ + + ]: 156326 : if (pending_pm_reload_request)
1717 : 167 : process_pm_reload_request();
1718 [ + + ]: 156326 : if (pending_pm_child_exit)
1719 : 25685 : process_pm_child_exit();
1720 [ + + ]: 155322 : if (pending_pm_pmsignal)
1721 : 114145 : process_pm_pmsignal();
1722 : :
1723 [ + + ]: 155322 : if (events[i].events & WL_SOCKET_ACCEPT)
1724 : : {
1725 : : ClientSocket s;
1726 : :
1727 [ + - ]: 15419 : if (AcceptConnection(events[i].fd, &s) == STATUS_OK)
1728 : 15419 : BackendStartup(&s);
1729 : :
1730 : : /* We no longer need the open socket in this process */
1731 [ + - ]: 15419 : if (s.sock != PGINVALID_SOCKET)
1732 : : {
1733 [ - + ]: 15419 : if (closesocket(s.sock) != 0)
1734 [ # # ]: 0 : elog(LOG, "could not close client socket: %m");
1735 : : }
1736 : : }
1737 : : }
1738 : :
1739 : : /*
1740 : : * If we need to launch any background processes after changing state
1741 : : * or because some exited, do so now.
1742 : : */
1743 : 155318 : LaunchMissingBackgroundProcesses();
1744 : :
1745 : : /* If we need to signal the autovacuum launcher, do so now */
1746 [ - + ]: 155318 : if (avlauncher_needs_signal)
1747 : : {
1748 : 0 : avlauncher_needs_signal = false;
1749 [ # # ]: 0 : if (AutoVacLauncherPMChild != NULL)
1750 : 0 : signal_child(AutoVacLauncherPMChild, SIGUSR2);
1751 : : }
1752 : :
1753 : : #ifdef HAVE_PTHREAD_IS_THREADED_NP
1754 : :
1755 : : /*
1756 : : * With assertions enabled, check regularly for appearance of
1757 : : * additional threads. All builds check at start and exit.
1758 : : */
1759 : : Assert(pthread_is_threaded_np() == 0);
1760 : : #endif
1761 : :
1762 : : /*
1763 : : * Lastly, check to see if it's time to do some things that we don't
1764 : : * want to do every single time through the loop, because they're a
1765 : : * bit expensive. Note that there's up to a minute of slop in when
1766 : : * these tasks will be performed, since DetermineSleepTime() will let
1767 : : * us sleep at most that long; except for SIGKILL timeout which has
1768 : : * special-case logic there.
1769 : : */
1770 : 155318 : now = time(NULL);
1771 : :
1772 : : /*
1773 : : * If we already sent SIGQUIT to children and they are slow to shut
1774 : : * down, it's time to send them SIGKILL (or SIGABRT if requested).
1775 : : * This doesn't happen normally, but under certain conditions backends
1776 : : * can get stuck while shutting down. This is a last measure to get
1777 : : * them unwedged.
1778 : : *
1779 : : * Note we also do this during recovery from a process crash.
1780 : : */
1781 [ + + + + ]: 155318 : if ((Shutdown >= ImmediateShutdown || FatalError) &&
1782 [ + + ]: 1665 : AbortStartTime != 0 &&
1783 [ - + ]: 1662 : (now - AbortStartTime) >= SIGKILL_CHILDREN_AFTER_SECS)
1784 : : {
1785 : : /* We were gentle with them before. Not anymore */
1786 [ # # # # ]: 0 : ereport(LOG,
1787 : : /* translator: %s is SIGKILL or SIGABRT */
1788 : : (errmsg("issuing %s to recalcitrant children",
1789 : : send_abort_for_kill ? "SIGABRT" : "SIGKILL")));
1790 [ # # ]: 0 : TerminateChildren(send_abort_for_kill ? SIGABRT : SIGKILL);
1791 : : /* reset flag so we don't SIGKILL again */
1792 : 0 : AbortStartTime = 0;
1793 : : }
1794 : :
1795 : : /*
1796 : : * Once a minute, verify that postmaster.pid hasn't been removed or
1797 : : * overwritten. If it has, we force a shutdown. This avoids having
1798 : : * postmasters and child processes hanging around after their database
1799 : : * is gone, and maybe causing problems if a new database cluster is
1800 : : * created in the same place. It also provides some protection
1801 : : * against a DBA foolishly removing postmaster.pid and manually
1802 : : * starting a new postmaster. Data corruption is likely to ensue from
1803 : : * that anyway, but we can minimize the damage by aborting ASAP.
1804 : : */
1805 [ + + ]: 155318 : if (now - last_lockfile_recheck_time >= 1 * SECS_PER_MINUTE)
1806 : : {
1807 [ - + ]: 24 : if (!RecheckDataDirLockFile())
1808 : : {
1809 [ # # ]: 0 : ereport(LOG,
1810 : : (errmsg("performing immediate shutdown because data directory lock file is invalid")));
1811 : 0 : kill(MyProcPid, SIGQUIT);
1812 : : }
1813 : 24 : last_lockfile_recheck_time = now;
1814 : : }
1815 : :
1816 : : /*
1817 : : * Touch Unix socket and lock files every 58 minutes, to ensure that
1818 : : * they are not removed by overzealous /tmp-cleaning tasks. We assume
1819 : : * no one runs cleaners with cutoff times of less than an hour ...
1820 : : */
1821 [ - + ]: 155318 : if (now - last_touch_time >= 58 * SECS_PER_MINUTE)
1822 : : {
1823 : 0 : TouchSocketFiles();
1824 : 0 : TouchSocketLockFiles();
1825 : 0 : last_touch_time = now;
1826 : : }
1827 : : }
1828 : : }
1829 : :
1830 : : /*
1831 : : * canAcceptConnections --- check to see if database state allows connections
1832 : : * of the specified type. backend_type can be B_BACKEND or B_AUTOVAC_WORKER.
1833 : : * (Note that we don't yet know whether a normal B_BACKEND connection might
1834 : : * turn into a walsender.)
1835 : : */
1836 : : static CAC_state
1837 : 16994 : canAcceptConnections(BackendType backend_type)
1838 : : {
1839 : 16994 : CAC_state result = CAC_OK;
1840 : :
1841 : : Assert(backend_type == B_BACKEND || backend_type == B_AUTOVAC_WORKER);
1842 : :
1843 : : /*
1844 : : * Can't start backends when in startup/shutdown/inconsistent recovery
1845 : : * state. We treat autovac workers the same as user backends for this
1846 : : * purpose.
1847 : : */
1848 [ + + + + ]: 16994 : if (pmState != PM_RUN && pmState != PM_HOT_STANDBY)
1849 : : {
1850 [ + + ]: 232 : if (Shutdown > NoShutdown)
1851 : 49 : return CAC_SHUTDOWN; /* shutdown is pending */
1852 [ + - + + ]: 183 : else if (!FatalError && pmState == PM_STARTUP)
1853 : 176 : return CAC_STARTUP; /* normal startup */
1854 [ + - + - ]: 7 : else if (!FatalError && pmState == PM_RECOVERY)
1855 : 7 : return CAC_NOTHOTSTANDBY; /* not yet ready for hot standby */
1856 : : else
1857 : 0 : return CAC_RECOVERY; /* else must be crash recovery */
1858 : : }
1859 : :
1860 : : /*
1861 : : * "Smart shutdown" restrictions are applied only to normal connections,
1862 : : * not to autovac workers.
1863 : : */
1864 [ - + - - ]: 16762 : if (!connsAllowed && backend_type == B_BACKEND)
1865 : 0 : return CAC_SHUTDOWN; /* shutdown is pending */
1866 : :
1867 : 16762 : return result;
1868 : : }
1869 : :
1870 : : /*
1871 : : * ClosePostmasterPorts -- close all the postmaster's open sockets
1872 : : *
1873 : : * This is called during child process startup to release file descriptors
1874 : : * that are not needed by that child process. The postmaster still has
1875 : : * them open, of course.
1876 : : *
1877 : : * Note: we pass am_syslogger as a boolean because we don't want to set
1878 : : * the global variable yet when this is called.
1879 : : */
1880 : : void
1881 : 24944 : ClosePostmasterPorts(bool am_syslogger)
1882 : : {
1883 : : /* Release resources held by the postmaster's WaitEventSet. */
1884 [ + + ]: 24944 : if (pm_wait_set)
1885 : : {
1886 : 21431 : FreeWaitEventSetAfterFork(pm_wait_set);
1887 : 21431 : pm_wait_set = NULL;
1888 : : }
1889 : :
1890 : : #ifndef WIN32
1891 : :
1892 : : /*
1893 : : * Close the write end of postmaster death watch pipe. It's important to
1894 : : * do this as early as possible, so that if postmaster dies, others won't
1895 : : * think that it's still running because we're holding the pipe open.
1896 : : */
1897 [ - + ]: 24944 : if (close(postmaster_alive_fds[POSTMASTER_FD_OWN]) != 0)
1898 [ # # ]: 0 : ereport(FATAL,
1899 : : (errcode_for_file_access(),
1900 : : errmsg_internal("could not close postmaster death monitoring pipe in child process: %m")));
1901 : 24944 : postmaster_alive_fds[POSTMASTER_FD_OWN] = -1;
1902 : : /* Notify fd.c that we released one pipe FD. */
1903 : 24944 : ReleaseExternalFD();
1904 : : #endif
1905 : :
1906 : : /*
1907 : : * Close the postmaster's listen sockets. These aren't tracked by fd.c,
1908 : : * so we don't call ReleaseExternalFD() here.
1909 : : *
1910 : : * The listen sockets are marked as FD_CLOEXEC, so this isn't needed in
1911 : : * EXEC_BACKEND mode.
1912 : : */
1913 : : #ifndef EXEC_BACKEND
1914 [ + + ]: 24944 : if (ListenSockets)
1915 : : {
1916 [ + + ]: 50535 : for (int i = 0; i < NumListenSockets; i++)
1917 : : {
1918 [ - + ]: 25592 : if (closesocket(ListenSockets[i]) != 0)
1919 [ # # ]: 0 : elog(LOG, "could not close listen socket: %m");
1920 : : }
1921 : 24943 : pfree(ListenSockets);
1922 : : }
1923 : 24944 : NumListenSockets = 0;
1924 : 24944 : ListenSockets = NULL;
1925 : : #endif
1926 : :
1927 : : /*
1928 : : * If using syslogger, close the read side of the pipe. We don't bother
1929 : : * tracking this in fd.c, either.
1930 : : */
1931 [ + + ]: 24944 : if (!am_syslogger)
1932 : : {
1933 : : #ifndef WIN32
1934 [ + + ]: 24943 : if (syslogPipe[0] >= 0)
1935 : 16 : close(syslogPipe[0]);
1936 : 24943 : syslogPipe[0] = -1;
1937 : : #else
1938 : : if (syslogPipe[0])
1939 : : CloseHandle(syslogPipe[0]);
1940 : : syslogPipe[0] = 0;
1941 : : #endif
1942 : : }
1943 : :
1944 : : #ifdef USE_BONJOUR
1945 : : /* If using Bonjour, close the connection to the mDNS daemon */
1946 : : if (bonjour_sdref)
1947 : : close(DNSServiceRefSockFD(bonjour_sdref));
1948 : : #endif
1949 : 24944 : }
1950 : :
1951 : :
1952 : : /*
1953 : : * InitProcessGlobals -- set MyStartTime[stamp], random seeds
1954 : : *
1955 : : * Called early in the postmaster and every backend.
1956 : : */
1957 : : void
1958 : 26243 : InitProcessGlobals(void)
1959 : : {
1960 : 26243 : MyStartTimestamp = GetCurrentTimestamp();
1961 : 26243 : MyStartTime = timestamptz_to_time_t(MyStartTimestamp);
1962 : :
1963 : : /* initialize timing infrastructure (required for INSTR_* calls) */
1964 : 26243 : pg_initialize_timing();
1965 : :
1966 : : /*
1967 : : * Set a different global seed in every process. We want something
1968 : : * unpredictable, so if possible, use high-quality random bits for the
1969 : : * seed. Otherwise, fall back to a seed based on timestamp and PID.
1970 : : */
1971 [ + - - + ]: 26243 : if (unlikely(!pg_prng_strong_seed(&pg_global_prng_state)))
1972 : : {
1973 : : uint64 rseed;
1974 : :
1975 : : /*
1976 : : * Since PIDs and timestamps tend to change more frequently in their
1977 : : * least significant bits, shift the timestamp left to allow a larger
1978 : : * total number of seeds in a given time period. Since that would
1979 : : * leave only 20 bits of the timestamp that cycle every ~1 second,
1980 : : * also mix in some higher bits.
1981 : : */
1982 : 0 : rseed = ((uint64) MyProcPid) ^
1983 : 0 : ((uint64) MyStartTimestamp << 12) ^
1984 : 0 : ((uint64) MyStartTimestamp >> 20);
1985 : :
1986 : 0 : pg_prng_seed(&pg_global_prng_state, rseed);
1987 : : }
1988 : :
1989 : : /*
1990 : : * Also make sure that we've set a good seed for random(3). Use of that
1991 : : * is deprecated in core Postgres, but extensions might use it.
1992 : : */
1993 : : #ifndef WIN32
1994 : 26243 : srandom(pg_prng_uint32(&pg_global_prng_state));
1995 : : #endif
1996 : 26243 : }
1997 : :
1998 : : /*
1999 : : * Child processes use SIGUSR1 to notify us of 'pmsignals'. pg_ctl uses
2000 : : * SIGUSR1 to ask postmaster to check for logrotate and promote files.
2001 : : */
2002 : : static void
2003 : 114443 : handle_pm_pmsignal_signal(SIGNAL_ARGS)
2004 : : {
2005 : 114443 : pending_pm_pmsignal = true;
2006 : 114443 : SetLatch(MyLatch);
2007 : 114443 : }
2008 : :
2009 : : /*
2010 : : * pg_ctl uses SIGHUP to request a reload of the configuration files.
2011 : : */
2012 : : static void
2013 : 167 : handle_pm_reload_request_signal(SIGNAL_ARGS)
2014 : : {
2015 : 167 : pending_pm_reload_request = true;
2016 : 167 : SetLatch(MyLatch);
2017 : 167 : }
2018 : :
2019 : : /*
2020 : : * Re-read config files, and tell children to do same.
2021 : : */
2022 : : static void
2023 : 167 : process_pm_reload_request(void)
2024 : : {
2025 : 167 : pending_pm_reload_request = false;
2026 : :
2027 [ + + ]: 167 : ereport(DEBUG2,
2028 : : (errmsg_internal("postmaster received reload request signal")));
2029 : :
2030 [ + - ]: 167 : if (Shutdown <= SmartShutdown)
2031 : : {
2032 [ + - ]: 167 : ereport(LOG,
2033 : : (errmsg("received SIGHUP, reloading configuration files")));
2034 : 167 : ProcessConfigFile(PGC_SIGHUP);
2035 : 167 : SignalChildren(SIGHUP, btmask_all_except(B_DEAD_END_BACKEND));
2036 : :
2037 : : /* Reload authentication config files too */
2038 [ - + ]: 167 : if (!load_hba())
2039 [ # # ]: 0 : ereport(LOG,
2040 : : /* translator: %s is a configuration file */
2041 : : (errmsg("%s was not reloaded", HbaFileName)));
2042 : :
2043 [ - + ]: 167 : if (!load_ident())
2044 [ # # ]: 0 : ereport(LOG,
2045 : : (errmsg("%s was not reloaded", IdentFileName)));
2046 : :
2047 : : #ifdef USE_SSL
2048 : : /* Reload SSL configuration as well */
2049 [ + + ]: 167 : if (EnableSSL)
2050 : : {
2051 [ + + ]: 14 : if (secure_initialize(false) == 0)
2052 : 12 : LoadedSSL = true;
2053 : : else
2054 [ + - ]: 2 : ereport(LOG,
2055 : : (errmsg("SSL configuration was not reloaded")));
2056 : : }
2057 : : else
2058 : : {
2059 : 153 : secure_destroy();
2060 : 153 : LoadedSSL = false;
2061 : : }
2062 : : #endif
2063 : :
2064 : : #ifdef EXEC_BACKEND
2065 : : /* Update the starting-point file for future children */
2066 : : write_nondefault_variables(PGC_SIGHUP);
2067 : : #endif
2068 : : }
2069 : 167 : }
2070 : :
2071 : : /*
2072 : : * pg_ctl uses SIGTERM, SIGINT and SIGQUIT to request different types of
2073 : : * shutdown.
2074 : : */
2075 : : static void
2076 : 993 : handle_pm_shutdown_request_signal(SIGNAL_ARGS)
2077 : : {
2078 [ + + + - ]: 993 : switch (postgres_signal_arg)
2079 : : {
2080 : 48 : case SIGTERM:
2081 : : /* smart is implied if the other two flags aren't set */
2082 : 48 : pending_pm_shutdown_request = true;
2083 : 48 : break;
2084 : 591 : case SIGINT:
2085 : 591 : pending_pm_fast_shutdown_request = true;
2086 : 591 : pending_pm_shutdown_request = true;
2087 : 591 : break;
2088 : 354 : case SIGQUIT:
2089 : 354 : pending_pm_immediate_shutdown_request = true;
2090 : 354 : pending_pm_shutdown_request = true;
2091 : 354 : break;
2092 : : }
2093 : 993 : SetLatch(MyLatch);
2094 : 993 : }
2095 : :
2096 : : /*
2097 : : * Process shutdown request.
2098 : : */
2099 : : static void
2100 : 993 : process_pm_shutdown_request(void)
2101 : : {
2102 : : int mode;
2103 : :
2104 [ + + ]: 993 : ereport(DEBUG2,
2105 : : (errmsg_internal("postmaster received shutdown request signal")));
2106 : :
2107 : 993 : pending_pm_shutdown_request = false;
2108 : :
2109 : : /*
2110 : : * If more than one shutdown request signal arrived since the last server
2111 : : * loop, take the one that is the most immediate. That matches the
2112 : : * priority that would apply if we processed them one by one in any order.
2113 : : */
2114 [ + + ]: 993 : if (pending_pm_immediate_shutdown_request)
2115 : : {
2116 : 354 : pending_pm_immediate_shutdown_request = false;
2117 : 354 : pending_pm_fast_shutdown_request = false;
2118 : 354 : mode = ImmediateShutdown;
2119 : : }
2120 [ + + ]: 639 : else if (pending_pm_fast_shutdown_request)
2121 : : {
2122 : 591 : pending_pm_fast_shutdown_request = false;
2123 : 591 : mode = FastShutdown;
2124 : : }
2125 : : else
2126 : 48 : mode = SmartShutdown;
2127 : :
2128 [ + + + - ]: 993 : switch (mode)
2129 : : {
2130 : 48 : case SmartShutdown:
2131 : :
2132 : : /*
2133 : : * Smart Shutdown:
2134 : : *
2135 : : * Wait for children to end their work, then shut down.
2136 : : */
2137 [ - + ]: 48 : if (Shutdown >= SmartShutdown)
2138 : 0 : break;
2139 : 48 : Shutdown = SmartShutdown;
2140 [ + - ]: 48 : ereport(LOG,
2141 : : (errmsg("received smart shutdown request")));
2142 : :
2143 : : /* Report status */
2144 : 48 : AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_STOPPING);
2145 : : #ifdef USE_SYSTEMD
2146 : : sd_notify(0, "STOPPING=1");
2147 : : #endif
2148 : :
2149 : : /*
2150 : : * If we reached normal running, we go straight to waiting for
2151 : : * client backends to exit. If already in PM_STOP_BACKENDS or a
2152 : : * later state, do not change it.
2153 : : */
2154 [ - + - - ]: 48 : if (pmState == PM_RUN || pmState == PM_HOT_STANDBY)
2155 : 48 : connsAllowed = false;
2156 [ # # # # ]: 0 : else if (pmState == PM_STARTUP || pmState == PM_RECOVERY)
2157 : : {
2158 : : /* There should be no clients, so proceed to stop children */
2159 : 0 : UpdatePMState(PM_STOP_BACKENDS);
2160 : : }
2161 : :
2162 : : /*
2163 : : * Now wait for online backup mode to end and backends to exit. If
2164 : : * that is already the case, PostmasterStateMachine will take the
2165 : : * next step.
2166 : : */
2167 : 48 : PostmasterStateMachine();
2168 : 48 : break;
2169 : :
2170 : 591 : case FastShutdown:
2171 : :
2172 : : /*
2173 : : * Fast Shutdown:
2174 : : *
2175 : : * Abort all children with SIGTERM (rollback active transactions
2176 : : * and exit) and shut down when they are gone.
2177 : : */
2178 [ - + ]: 591 : if (Shutdown >= FastShutdown)
2179 : 0 : break;
2180 : 591 : Shutdown = FastShutdown;
2181 [ + - ]: 591 : ereport(LOG,
2182 : : (errmsg("received fast shutdown request")));
2183 : :
2184 : : /* Report status */
2185 : 591 : AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_STOPPING);
2186 : : #ifdef USE_SYSTEMD
2187 : : sd_notify(0, "STOPPING=1");
2188 : : #endif
2189 : :
2190 [ + - - + ]: 591 : if (pmState == PM_STARTUP || pmState == PM_RECOVERY)
2191 : : {
2192 : : /* Just shut down background processes silently */
2193 : 0 : UpdatePMState(PM_STOP_BACKENDS);
2194 : : }
2195 [ + + ]: 591 : else if (pmState == PM_RUN ||
2196 [ + - ]: 63 : pmState == PM_HOT_STANDBY)
2197 : : {
2198 : : /* Report that we're about to zap live client sessions */
2199 [ + - ]: 591 : ereport(LOG,
2200 : : (errmsg("aborting any active transactions")));
2201 : 591 : UpdatePMState(PM_STOP_BACKENDS);
2202 : : }
2203 : :
2204 : : /*
2205 : : * PostmasterStateMachine will issue any necessary signals, or
2206 : : * take the next step if no child processes need to be killed.
2207 : : */
2208 : 591 : PostmasterStateMachine();
2209 : 591 : break;
2210 : :
2211 : 354 : case ImmediateShutdown:
2212 : :
2213 : : /*
2214 : : * Immediate Shutdown:
2215 : : *
2216 : : * abort all children with SIGQUIT, wait for them to exit,
2217 : : * terminate remaining ones with SIGKILL, then exit without
2218 : : * attempt to properly shut down the data base system.
2219 : : */
2220 [ - + ]: 354 : if (Shutdown >= ImmediateShutdown)
2221 : 0 : break;
2222 : 354 : Shutdown = ImmediateShutdown;
2223 [ + - ]: 354 : ereport(LOG,
2224 : : (errmsg("received immediate shutdown request")));
2225 : :
2226 : : /* Report status */
2227 : 354 : AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_STOPPING);
2228 : : #ifdef USE_SYSTEMD
2229 : : sd_notify(0, "STOPPING=1");
2230 : : #endif
2231 : :
2232 : : /* tell children to shut down ASAP */
2233 : : /* (note we don't apply send_abort_for_crash here) */
2234 : 354 : SetQuitSignalReason(PMQUIT_FOR_STOP);
2235 : 354 : TerminateChildren(SIGQUIT);
2236 : 354 : UpdatePMState(PM_WAIT_BACKENDS);
2237 : :
2238 : : /* set stopwatch for them to die */
2239 : 354 : AbortStartTime = time(NULL);
2240 : :
2241 : : /*
2242 : : * Now wait for backends to exit. If there are none,
2243 : : * PostmasterStateMachine will take the next step.
2244 : : */
2245 : 354 : PostmasterStateMachine();
2246 : 354 : break;
2247 : : }
2248 : 993 : }
2249 : :
2250 : : static void
2251 : 25771 : handle_pm_child_exit_signal(SIGNAL_ARGS)
2252 : : {
2253 : 25771 : pending_pm_child_exit = true;
2254 : 25771 : SetLatch(MyLatch);
2255 : 25771 : }
2256 : :
2257 : : /*
2258 : : * Cleanup after a child process dies.
2259 : : */
2260 : : static void
2261 : 25685 : process_pm_child_exit(void)
2262 : : {
2263 : : int pid; /* process id of dead child process */
2264 : : int exitstatus; /* its exit status */
2265 : :
2266 : 25685 : pending_pm_child_exit = false;
2267 : :
2268 [ - + ]: 25685 : ereport(DEBUG4,
2269 : : (errmsg_internal("reaping dead processes")));
2270 : :
2271 [ + + ]: 53334 : while ((pid = waitpid(-1, &exitstatus, WNOHANG)) > 0)
2272 : : {
2273 : : PMChild *pmchild;
2274 : :
2275 : : /*
2276 : : * Check if this child was a startup process.
2277 : : */
2278 [ + + + + ]: 27649 : if (StartupPMChild && pid == StartupPMChild->pid)
2279 : : {
2280 : 1009 : ReleasePostmasterChildSlot(StartupPMChild);
2281 : 1009 : StartupPMChild = NULL;
2282 : :
2283 : : /*
2284 : : * Startup process exited in response to a shutdown request (or it
2285 : : * completed normally regardless of the shutdown request).
2286 : : */
2287 [ + + ]: 1009 : if (Shutdown > NoShutdown &&
2288 [ + - + - : 112 : (EXIT_STATUS_0(exitstatus) || EXIT_STATUS_1(exitstatus)))
+ + ]
2289 : : {
2290 : 63 : StartupStatus = STARTUP_NOT_RUNNING;
2291 : 63 : UpdatePMState(PM_WAIT_BACKENDS);
2292 : : /* PostmasterStateMachine logic does the rest */
2293 : 63 : continue;
2294 : : }
2295 : :
2296 [ + - - + ]: 946 : if (EXIT_STATUS_3(exitstatus))
2297 : : {
2298 [ # # ]: 0 : ereport(LOG,
2299 : : (errmsg("shutdown at recovery target")));
2300 : 0 : StartupStatus = STARTUP_NOT_RUNNING;
2301 : 0 : Shutdown = Max(Shutdown, SmartShutdown);
2302 : 0 : TerminateChildren(SIGTERM);
2303 : 0 : UpdatePMState(PM_WAIT_BACKENDS);
2304 : : /* PostmasterStateMachine logic does the rest */
2305 : 0 : continue;
2306 : : }
2307 : :
2308 : : /*
2309 : : * Any unexpected exit (including FATAL exit) of the startup
2310 : : * process is catastrophic, so kill other children, and set
2311 : : * StartupStatus so we don't try to reinitialize after they're
2312 : : * gone. Exception: if StartupStatus is STARTUP_SIGNALED, then we
2313 : : * previously sent the startup process a SIGQUIT; so that's
2314 : : * probably the reason it died, and we do want to try to restart
2315 : : * in that case.
2316 : : *
2317 : : * This stanza also handles the case where we sent a SIGQUIT
2318 : : * during PM_STARTUP due to some dead-end child crashing: in that
2319 : : * situation, if the startup process dies on the SIGQUIT, we need
2320 : : * to transition to PM_WAIT_BACKENDS state which will allow
2321 : : * PostmasterStateMachine to restart the startup process. (On the
2322 : : * other hand, the startup process might complete normally, if we
2323 : : * were too late with the SIGQUIT. In that case we'll fall
2324 : : * through and commence normal operations.)
2325 : : */
2326 [ + + ]: 946 : if (!EXIT_STATUS_0(exitstatus))
2327 : : {
2328 [ + + ]: 60 : if (StartupStatus == STARTUP_SIGNALED)
2329 : : {
2330 : 49 : StartupStatus = STARTUP_NOT_RUNNING;
2331 [ - + ]: 49 : if (pmState == PM_STARTUP)
2332 : 0 : UpdatePMState(PM_WAIT_BACKENDS);
2333 : : }
2334 : : else
2335 : 11 : StartupStatus = STARTUP_CRASHED;
2336 : 60 : HandleChildCrash(pid, exitstatus,
2337 : 60 : _("startup process"));
2338 : 60 : continue;
2339 : : }
2340 : :
2341 : : /*
2342 : : * Startup succeeded, commence normal operations
2343 : : */
2344 : 886 : StartupStatus = STARTUP_NOT_RUNNING;
2345 : 886 : FatalError = false;
2346 : 886 : AbortStartTime = 0;
2347 : 886 : ReachedNormalRunning = true;
2348 : 886 : UpdatePMState(PM_RUN);
2349 : 886 : connsAllowed = true;
2350 : :
2351 : : /*
2352 : : * At the next iteration of the postmaster's main loop, we will
2353 : : * crank up the background tasks like the autovacuum launcher and
2354 : : * background workers that were not started earlier already.
2355 : : */
2356 : 886 : StartWorkerNeeded = true;
2357 : :
2358 : : /* at this point we are really open for business */
2359 [ + - ]: 886 : ereport(LOG,
2360 : : (errmsg("database system is ready to accept connections")));
2361 : :
2362 : : /* Report status */
2363 : 886 : AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_READY);
2364 : : #ifdef USE_SYSTEMD
2365 : : sd_notify(0, "READY=1");
2366 : : #endif
2367 : :
2368 : 886 : continue;
2369 : : }
2370 : :
2371 : : /*
2372 : : * Was it the bgwriter? Normal exit can be ignored; we'll start a new
2373 : : * one at the next iteration of the postmaster's main loop, if
2374 : : * necessary. Any other exit condition is treated as a crash.
2375 : : */
2376 [ + + + + ]: 26640 : if (BgWriterPMChild && pid == BgWriterPMChild->pid)
2377 : : {
2378 : 1009 : ReleasePostmasterChildSlot(BgWriterPMChild);
2379 : 1009 : BgWriterPMChild = NULL;
2380 [ + + ]: 1009 : if (!EXIT_STATUS_0(exitstatus))
2381 : 370 : HandleChildCrash(pid, exitstatus,
2382 : 370 : _("background writer process"));
2383 : 1009 : continue;
2384 : : }
2385 : :
2386 : : /*
2387 : : * Was it the checkpointer?
2388 : : */
2389 [ + + + + ]: 25631 : if (CheckpointerPMChild && pid == CheckpointerPMChild->pid)
2390 : : {
2391 : 1009 : ReleasePostmasterChildSlot(CheckpointerPMChild);
2392 : 1009 : CheckpointerPMChild = NULL;
2393 [ + + + - ]: 1009 : if (EXIT_STATUS_0(exitstatus) && pmState == PM_WAIT_CHECKPOINTER)
2394 : 639 : {
2395 : : /*
2396 : : * OK, we saw normal exit of the checkpointer after it's been
2397 : : * told to shut down. We know checkpointer wrote a shutdown
2398 : : * checkpoint, otherwise we'd still be in
2399 : : * PM_WAIT_XLOG_SHUTDOWN state.
2400 : : *
2401 : : * At this point only dead-end children and logger should be
2402 : : * left.
2403 : : */
2404 : 639 : UpdatePMState(PM_WAIT_DEAD_END);
2405 : 639 : ConfigurePostmasterWaitSet(false);
2406 : 639 : SignalChildren(SIGTERM, btmask_all_except(B_LOGGER));
2407 : : }
2408 : : else
2409 : : {
2410 : : /*
2411 : : * Any unexpected exit of the checkpointer (including FATAL
2412 : : * exit) is treated as a crash.
2413 : : */
2414 : 370 : HandleChildCrash(pid, exitstatus,
2415 : 370 : _("checkpointer process"));
2416 : : }
2417 : :
2418 : 1009 : continue;
2419 : : }
2420 : :
2421 : : /*
2422 : : * Was it the wal writer? Normal exit can be ignored; we'll start a
2423 : : * new one at the next iteration of the postmaster's main loop, if
2424 : : * necessary. Any other exit condition is treated as a crash.
2425 : : */
2426 [ + + + + ]: 24622 : if (WalWriterPMChild && pid == WalWriterPMChild->pid)
2427 : : {
2428 : 886 : ReleasePostmasterChildSlot(WalWriterPMChild);
2429 : 886 : WalWriterPMChild = NULL;
2430 [ + + ]: 886 : if (!EXIT_STATUS_0(exitstatus))
2431 : 310 : HandleChildCrash(pid, exitstatus,
2432 : 310 : _("WAL writer process"));
2433 : 886 : continue;
2434 : : }
2435 : :
2436 : : /*
2437 : : * Was it the wal receiver? If exit status is zero (normal) or one
2438 : : * (FATAL exit), we assume everything is all right just like normal
2439 : : * backends. (If we need a new wal receiver, we'll start one at the
2440 : : * next iteration of the postmaster's main loop.)
2441 : : */
2442 [ + + + + ]: 23736 : if (WalReceiverPMChild && pid == WalReceiverPMChild->pid)
2443 : : {
2444 : 274 : ReleasePostmasterChildSlot(WalReceiverPMChild);
2445 : 274 : WalReceiverPMChild = NULL;
2446 [ + - + - : 274 : if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
+ + ]
2447 : 18 : HandleChildCrash(pid, exitstatus,
2448 : 18 : _("WAL receiver process"));
2449 : 274 : continue;
2450 : : }
2451 : :
2452 : : /*
2453 : : * Was it the wal summarizer? Normal exit can be ignored; we'll start
2454 : : * a new one at the next iteration of the postmaster's main loop, if
2455 : : * necessary. Any other exit condition is treated as a crash.
2456 : : */
2457 [ + + + + ]: 23462 : if (WalSummarizerPMChild && pid == WalSummarizerPMChild->pid)
2458 : : {
2459 : 23 : ReleasePostmasterChildSlot(WalSummarizerPMChild);
2460 : 23 : WalSummarizerPMChild = NULL;
2461 [ + + ]: 23 : if (!EXIT_STATUS_0(exitstatus))
2462 : 18 : HandleChildCrash(pid, exitstatus,
2463 : 18 : _("WAL summarizer process"));
2464 : 23 : continue;
2465 : : }
2466 : :
2467 : : /*
2468 : : * Was it the autovacuum launcher? Normal exit can be ignored; we'll
2469 : : * start a new one at the next iteration of the postmaster's main
2470 : : * loop, if necessary. Any other exit condition is treated as a
2471 : : * crash.
2472 : : */
2473 [ + + + + ]: 23439 : if (AutoVacLauncherPMChild && pid == AutoVacLauncherPMChild->pid)
2474 : : {
2475 : 741 : ReleasePostmasterChildSlot(AutoVacLauncherPMChild);
2476 : 741 : AutoVacLauncherPMChild = NULL;
2477 [ + + ]: 741 : if (!EXIT_STATUS_0(exitstatus))
2478 : 262 : HandleChildCrash(pid, exitstatus,
2479 : 262 : _("autovacuum launcher process"));
2480 : 741 : continue;
2481 : : }
2482 : :
2483 : : /*
2484 : : * Was it the archiver? If exit status is zero (normal) or one (FATAL
2485 : : * exit), we assume everything is all right just like normal backends
2486 : : * and just try to start a new one on the next cycle of the
2487 : : * postmaster's main loop, to retry archiving remaining files.
2488 : : */
2489 [ + + + + ]: 22698 : if (PgArchPMChild && pid == PgArchPMChild->pid)
2490 : : {
2491 : 60 : ReleasePostmasterChildSlot(PgArchPMChild);
2492 : 60 : PgArchPMChild = NULL;
2493 [ + + + - : 60 : if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
+ - ]
2494 : 41 : HandleChildCrash(pid, exitstatus,
2495 : 41 : _("archiver process"));
2496 : 60 : continue;
2497 : : }
2498 : :
2499 : : /* Was it the system logger? If so, try to start a new one */
2500 [ + + - + ]: 22638 : if (SysLoggerPMChild && pid == SysLoggerPMChild->pid)
2501 : : {
2502 : 0 : ReleasePostmasterChildSlot(SysLoggerPMChild);
2503 : 0 : SysLoggerPMChild = NULL;
2504 : :
2505 : : /* for safety's sake, launch new logger *first* */
2506 [ # # ]: 0 : if (Logging_collector)
2507 : 0 : StartSysLogger();
2508 : :
2509 [ # # ]: 0 : if (!EXIT_STATUS_0(exitstatus))
2510 : 0 : LogChildExit(LOG, _("system logger process"),
2511 : : pid, exitstatus);
2512 : 0 : continue;
2513 : : }
2514 : :
2515 : : /*
2516 : : * Was it the slot sync worker? Normal exit or FATAL exit can be
2517 : : * ignored (FATAL can be caused by libpqwalreceiver on receiving
2518 : : * shutdown request by the startup process during promotion); we'll
2519 : : * start a new one at the next iteration of the postmaster's main
2520 : : * loop, if necessary. Any other exit condition is treated as a crash.
2521 : : */
2522 [ + + + + ]: 22638 : if (SlotSyncWorkerPMChild && pid == SlotSyncWorkerPMChild->pid)
2523 : : {
2524 : 6 : ReleasePostmasterChildSlot(SlotSyncWorkerPMChild);
2525 : 6 : SlotSyncWorkerPMChild = NULL;
2526 [ + + + - : 6 : if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
- + ]
2527 : 0 : HandleChildCrash(pid, exitstatus,
2528 : 0 : _("slot sync worker process"));
2529 : 6 : continue;
2530 : : }
2531 : :
2532 : : /* Was it an IO worker? */
2533 [ + + ]: 22632 : if (maybe_reap_io_worker(pid))
2534 : : {
2535 [ + + + - : 2061 : if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
+ + ]
2536 : 743 : HandleChildCrash(pid, exitstatus, _("io worker"));
2537 : :
2538 : : /*
2539 : : * A worker that exited with an error might have brought the pool
2540 : : * size below io_min_workers, or allowed the queue to grow to the
2541 : : * point where another worker called for growth.
2542 : : *
2543 : : * In the common case that a worker timed out due to idleness, no
2544 : : * replacement needs to be started. maybe_start_io_workers() will
2545 : : * figure that out.
2546 : : */
2547 : 2061 : maybe_start_io_workers();
2548 : :
2549 : 2061 : continue;
2550 : : }
2551 : :
2552 : : /*
2553 : : * Was it a backend or a background worker?
2554 : : */
2555 : 20571 : pmchild = FindPostmasterChildByPid(pid);
2556 [ + - ]: 20571 : if (pmchild)
2557 : : {
2558 : 20571 : CleanupBackend(pmchild, exitstatus);
2559 : : }
2560 : :
2561 : : /*
2562 : : * We don't know anything about this child process. That's highly
2563 : : * unexpected, as we do track all the child processes that we fork.
2564 : : */
2565 : : else
2566 : : {
2567 [ # # # # : 0 : if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
# # ]
2568 : 0 : HandleChildCrash(pid, exitstatus, _("untracked child process"));
2569 : : else
2570 : 0 : LogChildExit(LOG, _("untracked child process"), pid, exitstatus);
2571 : : }
2572 : : } /* loop over pending child-death reports */
2573 : :
2574 : : /*
2575 : : * After cleaning out the SIGCHLD queue, see if we have any state changes
2576 : : * or actions to make.
2577 : : */
2578 : 25685 : PostmasterStateMachine();
2579 : 24681 : }
2580 : :
2581 : : /*
2582 : : * CleanupBackend -- cleanup after terminated backend or background worker.
2583 : : *
2584 : : * Remove all local state associated with the child process and release its
2585 : : * PMChild slot.
2586 : : */
2587 : : static void
2588 : 20571 : CleanupBackend(PMChild *bp,
2589 : : int exitstatus) /* child's exit status. */
2590 : : {
2591 : : char namebuf[MAXPGPATH];
2592 : : const char *procname;
2593 : 20571 : bool crashed = false;
2594 : 20571 : bool logged = false;
2595 : : pid_t bp_pid;
2596 : : bool bp_bgworker_notify;
2597 : : BackendType bp_bkend_type;
2598 : : RegisteredBgWorker *rw;
2599 : :
2600 : : /* Construct a process name for the log message */
2601 [ + + ]: 20571 : if (bp->bkend_type == B_BG_WORKER)
2602 : : {
2603 : 3577 : snprintf(namebuf, MAXPGPATH, _("background worker \"%s\""),
2604 : 3577 : bp->rw->rw_worker.bgw_type);
2605 : 3577 : procname = namebuf;
2606 : : }
2607 : : else
2608 : 16994 : procname = _(GetBackendTypeDesc(bp->bkend_type));
2609 : :
2610 : : /*
2611 : : * If a backend dies in an ugly way then we must signal all other backends
2612 : : * to quickdie. If exit status is zero (normal) or one (FATAL exit), we
2613 : : * assume everything is all right and proceed to remove the backend from
2614 : : * the active child list.
2615 : : */
2616 [ + + + + : 20571 : if (!EXIT_STATUS_0(exitstatus) && !EXIT_STATUS_1(exitstatus))
+ + ]
2617 : 660 : crashed = true;
2618 : :
2619 : : #ifdef WIN32
2620 : :
2621 : : /*
2622 : : * On win32, also treat ERROR_WAIT_NO_CHILDREN (128) as nonfatal case,
2623 : : * since that sometimes happens under load when the process fails to start
2624 : : * properly (long before it starts using shared memory). Microsoft reports
2625 : : * it is related to mutex failure:
2626 : : * http://archives.postgresql.org/pgsql-hackers/2010-09/msg00790.php
2627 : : */
2628 : : if (exitstatus == ERROR_WAIT_NO_CHILDREN)
2629 : : {
2630 : : LogChildExit(LOG, procname, bp->pid, exitstatus);
2631 : : logged = true;
2632 : : crashed = false;
2633 : : }
2634 : : #endif
2635 : :
2636 : : /*
2637 : : * Release the PMChild entry.
2638 : : *
2639 : : * If the process attached to shared memory, this also checks that it
2640 : : * detached cleanly.
2641 : : */
2642 : 20571 : bp_pid = bp->pid;
2643 : 20571 : bp_bgworker_notify = bp->bgworker_notify;
2644 : 20571 : bp_bkend_type = bp->bkend_type;
2645 : 20571 : rw = bp->rw;
2646 [ + + ]: 20571 : if (!ReleasePostmasterChildSlot(bp))
2647 : : {
2648 : : /*
2649 : : * Uh-oh, the child failed to clean itself up. Treat as a crash after
2650 : : * all.
2651 : : */
2652 : 395 : crashed = true;
2653 : : }
2654 : 20571 : bp = NULL;
2655 : :
2656 : : /*
2657 : : * In a crash case, exit immediately without resetting background worker
2658 : : * state. However, if restart_after_crash is enabled, the background
2659 : : * worker state (e.g., rw_pid) still needs be reset so the worker can
2660 : : * restart after crash recovery. This reset is handled in
2661 : : * ResetBackgroundWorkerCrashTimes(), not here.
2662 : : */
2663 [ + + ]: 20571 : if (crashed)
2664 : : {
2665 : 660 : HandleChildCrash(bp_pid, exitstatus, procname);
2666 : 660 : return;
2667 : : }
2668 : :
2669 : : /*
2670 : : * This backend may have been slated to receive SIGUSR1 when some
2671 : : * background worker started or stopped. Cancel those notifications, as
2672 : : * we don't want to signal PIDs that are not PostgreSQL backends. This
2673 : : * gets skipped in the (probably very common) case where the backend has
2674 : : * never requested any such notifications.
2675 : : */
2676 [ + + ]: 19911 : if (bp_bgworker_notify)
2677 : 349 : BackgroundWorkerStopNotifications(bp_pid);
2678 : :
2679 : : /*
2680 : : * If it was an autovacuum worker, wake up the launcher so that it can
2681 : : * immediately launch a new worker or rebalance to cost limit setting of
2682 : : * the remaining workers.
2683 : : */
2684 [ + + + + ]: 19911 : if (bp_bkend_type == B_AUTOVAC_WORKER && AutoVacLauncherPMChild != NULL)
2685 : 1573 : signal_child(AutoVacLauncherPMChild, SIGUSR2);
2686 : :
2687 : : /*
2688 : : * If it was a background worker, also update its RegisteredBgWorker
2689 : : * entry.
2690 : : */
2691 [ + + ]: 19911 : if (bp_bkend_type == B_BG_WORKER)
2692 : : {
2693 [ + + ]: 3247 : if (!EXIT_STATUS_0(exitstatus))
2694 : : {
2695 : : /* Record timestamp, so we know when to restart the worker. */
2696 : 853 : rw->rw_crashed_at = GetCurrentTimestamp();
2697 : : }
2698 : : else
2699 : : {
2700 : : /* Zero exit status means terminate */
2701 : 2394 : rw->rw_crashed_at = 0;
2702 : 2394 : rw->rw_terminate = true;
2703 : : }
2704 : :
2705 : 3247 : rw->rw_pid = 0;
2706 : 3247 : ReportBackgroundWorkerExit(rw); /* report child death */
2707 : :
2708 [ + - ]: 3247 : if (!logged)
2709 : : {
2710 [ + + ]: 3247 : LogChildExit(EXIT_STATUS_0(exitstatus) ? DEBUG1 : LOG,
2711 : : procname, bp_pid, exitstatus);
2712 : 3247 : logged = true;
2713 : : }
2714 : :
2715 : : /* have it be restarted */
2716 : 3247 : HaveCrashedWorker = true;
2717 : : }
2718 : :
2719 [ + + ]: 19911 : if (!logged)
2720 : 16664 : LogChildExit(DEBUG2, procname, bp_pid, exitstatus);
2721 : : }
2722 : :
2723 : : /*
2724 : : * Transition into FatalError state, in response to something bad having
2725 : : * happened. Commonly the caller will have logged the reason for entering
2726 : : * FatalError state.
2727 : : *
2728 : : * This should only be called when not already in FatalError or
2729 : : * ImmediateShutdown state.
2730 : : */
2731 : : static void
2732 : 16 : HandleFatalError(QuitSignalReason reason, bool consider_sigabrt)
2733 : : {
2734 : : int sigtosend;
2735 : :
2736 : : Assert(!FatalError);
2737 : : Assert(Shutdown != ImmediateShutdown);
2738 : :
2739 : 16 : SetQuitSignalReason(reason);
2740 : :
2741 [ + - - + ]: 16 : if (consider_sigabrt && send_abort_for_crash)
2742 : 0 : sigtosend = SIGABRT;
2743 : : else
2744 : 16 : sigtosend = SIGQUIT;
2745 : :
2746 : : /*
2747 : : * Signal all other child processes to exit.
2748 : : *
2749 : : * We could exclude dead-end children here, but at least when sending
2750 : : * SIGABRT it seems better to include them.
2751 : : */
2752 : 16 : TerminateChildren(sigtosend);
2753 : :
2754 : 16 : FatalError = true;
2755 : :
2756 : : /*
2757 : : * Choose the appropriate new state to react to the fatal error. Unless we
2758 : : * were already in the process of shutting down, we go through
2759 : : * PM_WAIT_BACKENDS. For errors during the shutdown sequence, we directly
2760 : : * switch to PM_WAIT_DEAD_END.
2761 : : */
2762 [ - + - - : 16 : switch (pmState)
- - ]
2763 : : {
2764 : 0 : case PM_INIT:
2765 : : /* shouldn't have any children */
2766 : : Assert(false);
2767 : 0 : break;
2768 : :
2769 : : /* wait for children to die */
2770 : 16 : case PM_STARTUP:
2771 : : case PM_RECOVERY:
2772 : : case PM_HOT_STANDBY:
2773 : : case PM_RUN:
2774 : : case PM_STOP_BACKENDS:
2775 : 16 : UpdatePMState(PM_WAIT_BACKENDS);
2776 : 16 : break;
2777 : :
2778 : 0 : case PM_WAIT_BACKENDS:
2779 : : /* there might be more backends to wait for */
2780 : 0 : break;
2781 : :
2782 : 0 : case PM_WAIT_XLOG_SHUTDOWN:
2783 : : case PM_WAIT_XLOG_ARCHIVAL:
2784 : : case PM_WAIT_CHECKPOINTER:
2785 : : case PM_WAIT_IO_WORKERS:
2786 : :
2787 : : /*
2788 : : * NB: Similar code exists in PostmasterStateMachine()'s handling
2789 : : * of FatalError in PM_STOP_BACKENDS/PM_WAIT_BACKENDS states.
2790 : : */
2791 : 0 : ConfigurePostmasterWaitSet(false);
2792 : 0 : UpdatePMState(PM_WAIT_DEAD_END);
2793 : 0 : break;
2794 : :
2795 : 0 : case PM_WAIT_DEAD_END:
2796 : : case PM_NO_CHILDREN:
2797 : 0 : break;
2798 : : }
2799 : :
2800 : : /*
2801 : : * .. and if this doesn't happen quickly enough, now the clock is ticking
2802 : : * for us to kill them without mercy.
2803 : : */
2804 [ + - ]: 16 : if (AbortStartTime == 0)
2805 : 16 : AbortStartTime = time(NULL);
2806 : 16 : }
2807 : :
2808 : : /*
2809 : : * HandleChildCrash -- cleanup after failed backend, bgwriter, checkpointer,
2810 : : * walwriter, autovacuum, archiver, slot sync worker, or background worker.
2811 : : *
2812 : : * The objectives here are to clean up our local state about the child
2813 : : * process, and to signal all other remaining children to quickdie.
2814 : : *
2815 : : * The caller has already released its PMChild slot.
2816 : : */
2817 : : static void
2818 : 2852 : HandleChildCrash(int pid, int exitstatus, const char *procname)
2819 : : {
2820 : : /*
2821 : : * We only log messages and send signals if this is the first process
2822 : : * crash and we're not doing an immediate shutdown; otherwise, we're only
2823 : : * here to update postmaster's idea of live processes. If we have already
2824 : : * signaled children, nonzero exit status is to be expected, so don't
2825 : : * clutter log.
2826 : : */
2827 [ + + + + ]: 2852 : if (FatalError || Shutdown == ImmediateShutdown)
2828 : 2836 : return;
2829 : :
2830 : 16 : LogChildExit(LOG, procname, pid, exitstatus);
2831 [ + - ]: 16 : ereport(LOG,
2832 : : (errmsg("terminating any other active server processes")));
2833 : :
2834 : : /*
2835 : : * Switch into error state. The crashed process has already been removed
2836 : : * from ActiveChildList.
2837 : : */
2838 : 16 : HandleFatalError(PMQUIT_FOR_CRASH, true);
2839 : : }
2840 : :
2841 : : /*
2842 : : * Log the death of a child process.
2843 : : */
2844 : : static void
2845 : 19927 : LogChildExit(int lev, const char *procname, int pid, int exitstatus)
2846 : : {
2847 : : /*
2848 : : * size of activity_buffer is arbitrary, but set equal to default
2849 : : * track_activity_query_size
2850 : : */
2851 : : char activity_buffer[1024];
2852 : 19927 : const char *activity = NULL;
2853 : :
2854 [ + + ]: 19927 : if (!EXIT_STATUS_0(exitstatus))
2855 : 1241 : activity = pgstat_get_crashed_backend_activity(pid,
2856 : : activity_buffer,
2857 : : sizeof(activity_buffer));
2858 : :
2859 [ + + ]: 19927 : if (WIFEXITED(exitstatus))
2860 [ + + + + ]: 19923 : ereport(lev,
2861 : :
2862 : : /*------
2863 : : translator: %s is a noun phrase describing a child process, such as
2864 : : "server process" */
2865 : : (errmsg("%s (PID %d) exited with exit code %d",
2866 : : procname, pid, WEXITSTATUS(exitstatus)),
2867 : : activity ? errdetail("Failed process was running: %s", activity) : 0));
2868 [ + - ]: 4 : else if (WIFSIGNALED(exitstatus))
2869 : : {
2870 : : #if defined(WIN32)
2871 : : ereport(lev,
2872 : :
2873 : : /*------
2874 : : translator: %s is a noun phrase describing a child process, such as
2875 : : "server process" */
2876 : : (errmsg("%s (PID %d) was terminated by exception 0x%X",
2877 : : procname, pid, WTERMSIG(exitstatus)),
2878 : : errhint("See C include file \"ntstatus.h\" for a description of the hexadecimal value."),
2879 : : activity ? errdetail("Failed process was running: %s", activity) : 0));
2880 : : #else
2881 [ + - + - ]: 4 : ereport(lev,
2882 : :
2883 : : /*------
2884 : : translator: %s is a noun phrase describing a child process, such as
2885 : : "server process" */
2886 : : (errmsg("%s (PID %d) was terminated by signal %d: %s",
2887 : : procname, pid, WTERMSIG(exitstatus),
2888 : : pg_strsignal(WTERMSIG(exitstatus))),
2889 : : activity ? errdetail("Failed process was running: %s", activity) : 0));
2890 : : #endif
2891 : : }
2892 : : else
2893 [ # # # # ]: 0 : ereport(lev,
2894 : :
2895 : : /*------
2896 : : translator: %s is a noun phrase describing a child process, such as
2897 : : "server process" */
2898 : : (errmsg("%s (PID %d) exited with unrecognized status %d",
2899 : : procname, pid, exitstatus),
2900 : : activity ? errdetail("Failed process was running: %s", activity) : 0));
2901 : 19927 : }
2902 : :
2903 : : /*
2904 : : * Advance the postmaster's state machine and take actions as appropriate
2905 : : *
2906 : : * This is common code for process_pm_shutdown_request(),
2907 : : * process_pm_child_exit() and process_pm_pmsignal(), which process the signals
2908 : : * that might mean we need to change state.
2909 : : */
2910 : : static void
2911 : 28711 : PostmasterStateMachine(void)
2912 : : {
2913 : : /* If we're doing a smart shutdown, try to advance that state. */
2914 [ + + + + ]: 28711 : if (pmState == PM_RUN || pmState == PM_HOT_STANDBY)
2915 : : {
2916 [ + + ]: 20675 : if (!connsAllowed)
2917 : : {
2918 : : /*
2919 : : * This state ends when we have no normal client backends running.
2920 : : * Then we're ready to stop other children.
2921 : : */
2922 [ + + ]: 125 : if (CountChildren(btmask(B_BACKEND)) == 0)
2923 : 48 : UpdatePMState(PM_STOP_BACKENDS);
2924 : : }
2925 : : }
2926 : :
2927 : : /*
2928 : : * In the PM_WAIT_BACKENDS state, wait for all the regular backends and
2929 : : * processes like autovacuum and background workers that are comparable to
2930 : : * backends to exit.
2931 : : *
2932 : : * PM_STOP_BACKENDS is a transient state that means the same as
2933 : : * PM_WAIT_BACKENDS, but we signal the processes first, before waiting for
2934 : : * them. Treating it as a distinct pmState allows us to share this code
2935 : : * across multiple shutdown code paths.
2936 : : */
2937 [ + + + + ]: 28711 : if (pmState == PM_STOP_BACKENDS || pmState == PM_WAIT_BACKENDS)
2938 : : {
2939 : 5398 : BackendTypeMask targetMask = BTYPE_MASK_NONE;
2940 : :
2941 : : /*
2942 : : * PM_WAIT_BACKENDS state ends when we have no regular backends, no
2943 : : * autovac launcher or workers, and no bgworkers (including
2944 : : * unconnected ones).
2945 : : */
2946 : 5398 : targetMask = btmask_add(targetMask,
2947 : : B_BACKEND,
2948 : : B_AUTOVAC_LAUNCHER,
2949 : : B_AUTOVAC_WORKER,
2950 : : B_BG_WORKER);
2951 : :
2952 : : /*
2953 : : * No walwriter, bgwriter, slot sync worker, or WAL summarizer either.
2954 : : */
2955 : 5398 : targetMask = btmask_add(targetMask,
2956 : : B_WAL_WRITER,
2957 : : B_BG_WRITER,
2958 : : B_SLOTSYNC_WORKER,
2959 : : B_WAL_SUMMARIZER);
2960 : :
2961 : : /* If we're in recovery, also stop startup and walreceiver procs */
2962 : 5398 : targetMask = btmask_add(targetMask,
2963 : : B_STARTUP,
2964 : : B_WAL_RECEIVER);
2965 : :
2966 : : /*
2967 : : * If we are doing crash recovery or an immediate shutdown then we
2968 : : * expect archiver, checkpointer, io workers and walsender to exit as
2969 : : * well, otherwise not.
2970 : : */
2971 [ + + + + ]: 5398 : if (FatalError || Shutdown >= ImmediateShutdown)
2972 : 2041 : targetMask = btmask_add(targetMask,
2973 : : B_CHECKPOINTER,
2974 : : B_ARCHIVER,
2975 : : B_IO_WORKER,
2976 : : B_WAL_SENDER);
2977 : :
2978 : : /*
2979 : : * Normally archiver, checkpointer, IO workers and walsenders will
2980 : : * continue running; they will be terminated later after writing the
2981 : : * checkpoint record. We also let dead-end children to keep running
2982 : : * for now. The syslogger process exits last.
2983 : : *
2984 : : * This assertion checks that we have covered all backend types,
2985 : : * either by including them in targetMask, or by noting here that they
2986 : : * are allowed to continue running.
2987 : : */
2988 : : #ifdef USE_ASSERT_CHECKING
2989 : : {
2990 : : BackendTypeMask remainMask = BTYPE_MASK_NONE;
2991 : :
2992 : : remainMask = btmask_add(remainMask,
2993 : : B_DEAD_END_BACKEND,
2994 : : B_LOGGER);
2995 : :
2996 : : /*
2997 : : * Archiver, checkpointer, IO workers, and walsender may or may
2998 : : * not be in targetMask already.
2999 : : */
3000 : : remainMask = btmask_add(remainMask,
3001 : : B_ARCHIVER,
3002 : : B_CHECKPOINTER,
3003 : : B_IO_WORKER,
3004 : : B_WAL_SENDER);
3005 : :
3006 : : /* these are not real postmaster children */
3007 : : remainMask = btmask_add(remainMask,
3008 : : B_INVALID,
3009 : : B_STANDALONE_BACKEND);
3010 : :
3011 : : /* also add data checksums processes */
3012 : : remainMask = btmask_add(remainMask,
3013 : : B_DATACHECKSUMSWORKER_LAUNCHER,
3014 : : B_DATACHECKSUMSWORKER_WORKER);
3015 : :
3016 : : /* All types should be included in targetMask or remainMask */
3017 : : Assert((remainMask.mask | targetMask.mask) == BTYPE_MASK_ALL.mask);
3018 : : }
3019 : : #endif
3020 : :
3021 : : /* If we had not yet signaled the processes to exit, do so now */
3022 [ + + ]: 5398 : if (pmState == PM_STOP_BACKENDS)
3023 : : {
3024 : : /*
3025 : : * Forget any pending requests for background workers, since we're
3026 : : * no longer willing to launch any new workers. (If additional
3027 : : * requests arrive, BackgroundWorkerStateChange will reject them.)
3028 : : */
3029 : 639 : ForgetUnstartedBackgroundWorkers();
3030 : :
3031 : 639 : SignalChildren(SIGTERM, targetMask);
3032 : :
3033 : 639 : UpdatePMState(PM_WAIT_BACKENDS);
3034 : : }
3035 : :
3036 : : /* Are any of the target processes still running? */
3037 [ + + ]: 5398 : if (CountChildren(targetMask) == 0)
3038 : : {
3039 [ + + + + ]: 1009 : if (Shutdown >= ImmediateShutdown || FatalError)
3040 : : {
3041 : : /*
3042 : : * Stop any dead-end children and stop creating new ones.
3043 : : *
3044 : : * NB: Similar code exists in HandleFatalError(), when the
3045 : : * error happens in pmState > PM_WAIT_BACKENDS.
3046 : : */
3047 : 370 : UpdatePMState(PM_WAIT_DEAD_END);
3048 : 370 : ConfigurePostmasterWaitSet(false);
3049 : 370 : SignalChildren(SIGQUIT, btmask(B_DEAD_END_BACKEND));
3050 : :
3051 : : /*
3052 : : * We already SIGQUIT'd auxiliary processes (other than
3053 : : * logger), if any, when we started immediate shutdown or
3054 : : * entered FatalError state.
3055 : : */
3056 : : }
3057 : : else
3058 : : {
3059 : : /*
3060 : : * If we get here, we are proceeding with normal shutdown. All
3061 : : * the regular children are gone, and it's time to tell the
3062 : : * checkpointer to do a shutdown checkpoint.
3063 : : */
3064 : : Assert(Shutdown > NoShutdown);
3065 : : /* Start the checkpointer if not running */
3066 [ - + ]: 639 : if (CheckpointerPMChild == NULL)
3067 : 0 : CheckpointerPMChild = StartChildProcess(B_CHECKPOINTER);
3068 : : /* And tell it to write the shutdown checkpoint */
3069 [ + - ]: 639 : if (CheckpointerPMChild != NULL)
3070 : : {
3071 : 639 : signal_child(CheckpointerPMChild, SIGINT);
3072 : 639 : UpdatePMState(PM_WAIT_XLOG_SHUTDOWN);
3073 : : }
3074 : : else
3075 : : {
3076 : : /*
3077 : : * If we failed to fork a checkpointer, just shut down.
3078 : : * Any required cleanup will happen at next restart. We
3079 : : * set FatalError so that an "abnormal shutdown" message
3080 : : * gets logged when we exit.
3081 : : *
3082 : : * We don't consult send_abort_for_crash here, as it's
3083 : : * unlikely that dumping cores would illuminate the reason
3084 : : * for checkpointer fork failure.
3085 : : *
3086 : : * XXX: It may be worth to introduce a different PMQUIT
3087 : : * value that signals that the cluster is in a bad state,
3088 : : * without a process having crashed. But right now this
3089 : : * path is very unlikely to be reached, so it isn't
3090 : : * obviously worthwhile adding a distinct error message in
3091 : : * quickdie().
3092 : : */
3093 : 0 : HandleFatalError(PMQUIT_FOR_CRASH, false);
3094 : : }
3095 : : }
3096 : : }
3097 : : }
3098 : :
3099 : : /*
3100 : : * The state transition from PM_WAIT_XLOG_SHUTDOWN to
3101 : : * PM_WAIT_XLOG_ARCHIVAL is in process_pm_pmsignal(), in response to
3102 : : * PMSIGNAL_XLOG_IS_SHUTDOWN.
3103 : : */
3104 : :
3105 [ + + ]: 28711 : if (pmState == PM_WAIT_XLOG_ARCHIVAL)
3106 : : {
3107 : : /*
3108 : : * PM_WAIT_XLOG_ARCHIVAL state ends when there are no children other
3109 : : * than checkpointer, io workers and dead-end children left. There
3110 : : * shouldn't be any regular backends left by now anyway; what we're
3111 : : * really waiting for is for walsenders and archiver to exit.
3112 : : */
3113 [ + + ]: 706 : if (CountChildren(btmask_all_except(B_CHECKPOINTER, B_IO_WORKER,
3114 : : B_LOGGER, B_DEAD_END_BACKEND)) == 0)
3115 : : {
3116 : 639 : UpdatePMState(PM_WAIT_IO_WORKERS);
3117 : 639 : SignalChildren(SIGUSR2, btmask(B_IO_WORKER));
3118 : : }
3119 : : }
3120 : :
3121 [ + + ]: 28711 : if (pmState == PM_WAIT_IO_WORKERS)
3122 : : {
3123 : : /*
3124 : : * PM_WAIT_IO_WORKERS state ends when there's only checkpointer and
3125 : : * dead-end children left.
3126 : : */
3127 [ + + ]: 1899 : if (io_worker_count == 0)
3128 : : {
3129 : 639 : UpdatePMState(PM_WAIT_CHECKPOINTER);
3130 : :
3131 : : /*
3132 : : * Now that the processes mentioned above are gone, tell
3133 : : * checkpointer to shut down too. That allows checkpointer to
3134 : : * perform some last bits of cleanup without other processes
3135 : : * interfering.
3136 : : */
3137 [ + - ]: 639 : if (CheckpointerPMChild != NULL)
3138 : 639 : signal_child(CheckpointerPMChild, SIGUSR2);
3139 : : }
3140 : : }
3141 : :
3142 : : /*
3143 : : * The state transition from PM_WAIT_CHECKPOINTER to PM_WAIT_DEAD_END is
3144 : : * in process_pm_child_exit().
3145 : : */
3146 : :
3147 [ + + ]: 28711 : if (pmState == PM_WAIT_DEAD_END)
3148 : : {
3149 : : /*
3150 : : * PM_WAIT_DEAD_END state ends when all other children are gone except
3151 : : * for the logger. During normal shutdown, all that remains are
3152 : : * dead-end backends, but in FatalError processing we jump straight
3153 : : * here with more processes remaining. Note that they have already
3154 : : * been sent appropriate shutdown signals, either during a normal
3155 : : * state transition leading up to PM_WAIT_DEAD_END, or during
3156 : : * FatalError processing.
3157 : : *
3158 : : * The reason we wait is to protect against a new postmaster starting
3159 : : * conflicting subprocesses; this isn't an ironclad protection, but it
3160 : : * at least helps in the shutdown-and-immediately-restart scenario.
3161 : : */
3162 [ + + ]: 1032 : if (CountChildren(btmask_all_except(B_LOGGER)) == 0)
3163 : : {
3164 : : /* These other guys should be dead already */
3165 : : Assert(StartupPMChild == NULL);
3166 : : Assert(WalReceiverPMChild == NULL);
3167 : : Assert(WalSummarizerPMChild == NULL);
3168 : : Assert(BgWriterPMChild == NULL);
3169 : : Assert(CheckpointerPMChild == NULL);
3170 : : Assert(WalWriterPMChild == NULL);
3171 : : Assert(AutoVacLauncherPMChild == NULL);
3172 : : Assert(SlotSyncWorkerPMChild == NULL);
3173 : : /* syslogger is not considered here */
3174 : 1009 : UpdatePMState(PM_NO_CHILDREN);
3175 : : }
3176 : : }
3177 : :
3178 : : /*
3179 : : * If we've been told to shut down, we exit as soon as there are no
3180 : : * remaining children. If there was a crash, cleanup will occur at the
3181 : : * next startup. (Before PostgreSQL 8.3, we tried to recover from the
3182 : : * crash before exiting, but that seems unwise if we are quitting because
3183 : : * we got SIGTERM from init --- there may well not be time for recovery
3184 : : * before init decides to SIGKILL us.)
3185 : : *
3186 : : * Note that the syslogger continues to run. It will exit when it sees
3187 : : * EOF on its input pipe, which happens when there are no more upstream
3188 : : * processes.
3189 : : */
3190 [ + + + + ]: 28711 : if (Shutdown > NoShutdown && pmState == PM_NO_CHILDREN)
3191 : : {
3192 [ - + ]: 993 : if (FatalError)
3193 : : {
3194 [ # # ]: 0 : ereport(LOG, (errmsg("abnormal database system shutdown")));
3195 : 0 : ExitPostmaster(1);
3196 : : }
3197 : : else
3198 : : {
3199 : : /*
3200 : : * Normal exit from the postmaster is here. We don't need to log
3201 : : * anything here, since the UnlinkLockFiles proc_exit callback
3202 : : * will do so, and that should be the last user-visible action.
3203 : : */
3204 : 993 : ExitPostmaster(0);
3205 : : }
3206 : : }
3207 : :
3208 : : /*
3209 : : * If the startup process failed, or the user does not want an automatic
3210 : : * restart after backend crashes, wait for all non-syslogger children to
3211 : : * exit, and then exit postmaster. We don't try to reinitialize when the
3212 : : * startup process fails, because more than likely it will just fail again
3213 : : * and we will keep trying forever.
3214 : : */
3215 [ + + ]: 27718 : if (pmState == PM_NO_CHILDREN)
3216 : : {
3217 [ + + ]: 16 : if (StartupStatus == STARTUP_CRASHED)
3218 : : {
3219 [ + - ]: 11 : ereport(LOG,
3220 : : (errmsg("shutting down due to startup process failure")));
3221 : 11 : ExitPostmaster(1);
3222 : : }
3223 [ - + ]: 5 : if (!restart_after_crash)
3224 : : {
3225 [ # # ]: 0 : ereport(LOG,
3226 : : (errmsg("shutting down because \"restart_after_crash\" is off")));
3227 : 0 : ExitPostmaster(1);
3228 : : }
3229 : : }
3230 : :
3231 : : /*
3232 : : * If we need to recover from a crash, wait for all non-syslogger children
3233 : : * to exit, then reset shmem and start the startup process.
3234 : : */
3235 [ + + + + ]: 27707 : if (FatalError && pmState == PM_NO_CHILDREN)
3236 : : {
3237 [ + - ]: 5 : ereport(LOG,
3238 : : (errmsg("all server processes terminated; reinitializing")));
3239 : :
3240 : : /* remove leftover temporary files after a crash */
3241 [ + + ]: 5 : if (remove_temp_files_after_crash)
3242 : 4 : RemovePgTempFiles();
3243 : :
3244 : : /* allow background workers to immediately restart */
3245 : 5 : ResetBackgroundWorkerCrashTimes();
3246 : :
3247 : 5 : shmem_exit(1);
3248 : :
3249 : : /* re-read control file into local memory */
3250 : 5 : LocalProcessControlFile(true);
3251 : :
3252 : : /*
3253 : : * Re-initialize shared memory and semaphores. Note: We don't call
3254 : : * RegisterBuiltinShmemCallbacks(), we keep the old registrations. In
3255 : : * order to re-register structs in extensions, we'd need to reload
3256 : : * shared preload libraries, and we don't want to do that.
3257 : : */
3258 : 5 : ResetShmemAllocator();
3259 : 5 : ShmemCallRequestCallbacks();
3260 : 5 : CreateSharedMemoryAndSemaphores();
3261 : :
3262 : 5 : UpdatePMState(PM_STARTUP);
3263 : :
3264 : : /* Make sure we can perform I/O while starting up. */
3265 : 5 : maybe_start_io_workers();
3266 : :
3267 : 5 : StartupPMChild = StartChildProcess(B_STARTUP);
3268 : : Assert(StartupPMChild != NULL);
3269 : 5 : StartupStatus = STARTUP_RUNNING;
3270 : : /* crash recovery started, reset SIGKILL flag */
3271 : 5 : AbortStartTime = 0;
3272 : :
3273 : : /* start accepting server socket connection events again */
3274 : 5 : ConfigurePostmasterWaitSet(true);
3275 : : }
3276 : 27707 : }
3277 : :
3278 : : static const char *
3279 : 1548 : pmstate_name(PMState state)
3280 : : {
3281 : : #define PM_TOSTR_CASE(sym) case sym: return #sym
3282 [ + + + + : 1548 : switch (state)
+ + + + +
+ + + +
- ]
3283 : : {
3284 : 83 : PM_TOSTR_CASE(PM_INIT);
3285 : 166 : PM_TOSTR_CASE(PM_STARTUP);
3286 : 28 : PM_TOSTR_CASE(PM_RECOVERY);
3287 : 25 : PM_TOSTR_CASE(PM_HOT_STANDBY);
3288 : 153 : PM_TOSTR_CASE(PM_RUN);
3289 : 132 : PM_TOSTR_CASE(PM_STOP_BACKENDS);
3290 : 178 : PM_TOSTR_CASE(PM_WAIT_BACKENDS);
3291 : 132 : PM_TOSTR_CASE(PM_WAIT_XLOG_SHUTDOWN);
3292 : 132 : PM_TOSTR_CASE(PM_WAIT_XLOG_ARCHIVAL);
3293 : 132 : PM_TOSTR_CASE(PM_WAIT_IO_WORKERS);
3294 : 170 : PM_TOSTR_CASE(PM_WAIT_DEAD_END);
3295 : 132 : PM_TOSTR_CASE(PM_WAIT_CHECKPOINTER);
3296 : 85 : PM_TOSTR_CASE(PM_NO_CHILDREN);
3297 : : }
3298 : : #undef PM_TOSTR_CASE
3299 : :
3300 : 0 : pg_unreachable();
3301 : : return ""; /* silence compiler */
3302 : : }
3303 : :
3304 : : /*
3305 : : * Simple wrapper for updating pmState. The main reason to have this wrapper
3306 : : * is that it makes it easy to log all state transitions.
3307 : : */
3308 : : static void
3309 : 8627 : UpdatePMState(PMState newState)
3310 : : {
3311 [ + + ]: 8627 : elog(DEBUG1, "updating PMState from %s to %s",
3312 : : pmstate_name(pmState), pmstate_name(newState));
3313 : 8627 : pmState = newState;
3314 : 8627 : }
3315 : :
3316 : : /*
3317 : : * Launch background processes after state change, or relaunch after an
3318 : : * existing process has exited.
3319 : : *
3320 : : * Check the current pmState and the status of any background processes. If
3321 : : * there are any background processes missing that should be running in the
3322 : : * current state, but are not, launch them.
3323 : : */
3324 : : static void
3325 : 155318 : LaunchMissingBackgroundProcesses(void)
3326 : : {
3327 : : /* Syslogger is active in all states */
3328 [ + + - + ]: 155318 : if (SysLoggerPMChild == NULL && Logging_collector)
3329 : 0 : StartSysLogger();
3330 : :
3331 : : /*
3332 : : * The number of configured workers might have changed, or a prior start
3333 : : * of a worker might have failed. Check if we need to start/stop any
3334 : : * workers.
3335 : : *
3336 : : * A config file change will always lead to this function being called, so
3337 : : * we always will process the config change in a timely manner.
3338 : : */
3339 : 155318 : maybe_start_io_workers();
3340 : :
3341 : : /*
3342 : : * The checkpointer and the background writer are active from the start,
3343 : : * until shutdown is initiated.
3344 : : *
3345 : : * (If the checkpointer is not running when we enter the
3346 : : * PM_WAIT_XLOG_SHUTDOWN state, it is launched one more time to perform
3347 : : * the shutdown checkpoint. That's done in PostmasterStateMachine(), not
3348 : : * here.)
3349 : : */
3350 [ + + + + ]: 155318 : if (pmState == PM_RUN || pmState == PM_RECOVERY ||
3351 [ + + + + ]: 9778 : pmState == PM_HOT_STANDBY || pmState == PM_STARTUP)
3352 : : {
3353 [ + + ]: 148241 : if (CheckpointerPMChild == NULL)
3354 : 5 : CheckpointerPMChild = StartChildProcess(B_CHECKPOINTER);
3355 [ + + ]: 148241 : if (BgWriterPMChild == NULL)
3356 : 5 : BgWriterPMChild = StartChildProcess(B_BG_WRITER);
3357 : : }
3358 : :
3359 : : /*
3360 : : * WAL writer is needed only in normal operation (else we cannot be
3361 : : * writing any new WAL).
3362 : : */
3363 [ + + + + ]: 155318 : if (WalWriterPMChild == NULL && pmState == PM_RUN)
3364 : 886 : WalWriterPMChild = StartChildProcess(B_WAL_WRITER);
3365 : :
3366 : : /*
3367 : : * We don't want autovacuum to run in binary upgrade mode because
3368 : : * autovacuum might update relfrozenxid for empty tables before the
3369 : : * physical files are put in place.
3370 : : */
3371 [ + + + + : 166343 : if (!IsBinaryUpgrade && AutoVacLauncherPMChild == NULL &&
+ + ]
3372 [ - + ]: 15623 : (AutoVacuumingActive() || start_autovac_launcher) &&
3373 [ + + ]: 6427 : pmState == PM_RUN)
3374 : : {
3375 : 741 : AutoVacLauncherPMChild = StartChildProcess(B_AUTOVAC_LAUNCHER);
3376 [ + - ]: 741 : if (AutoVacLauncherPMChild != NULL)
3377 : 741 : start_autovac_launcher = false; /* signal processed */
3378 : : }
3379 : :
3380 : : /*
3381 : : * If WAL archiving is enabled always, we are allowed to start archiver
3382 : : * even during recovery.
3383 : : */
3384 [ + + ]: 155318 : if (PgArchPMChild == NULL &&
3385 [ + + + + ]: 154095 : ((XLogArchivingActive() && pmState == PM_RUN) ||
3386 [ + + + - : 154095 : (XLogArchivingAlways() && (pmState == PM_RECOVERY || pmState == PM_HOT_STANDBY))) &&
- + + - ]
3387 : 57 : PgArchCanRestart())
3388 : 57 : PgArchPMChild = StartChildProcess(B_ARCHIVER);
3389 : :
3390 : : /*
3391 : : * If we need to start a slot sync worker, try to do that now
3392 : : *
3393 : : * We allow to start the slot sync worker when we are on a hot standby,
3394 : : * fast or immediate shutdown is not in progress, slot sync parameters are
3395 : : * configured correctly, and it is the first time of worker's launch, or
3396 : : * enough time has passed since the worker was launched last.
3397 : : */
3398 [ + + + + ]: 155318 : if (SlotSyncWorkerPMChild == NULL && pmState == PM_HOT_STANDBY &&
3399 [ + - + + : 2467 : Shutdown <= SmartShutdown && sync_replication_slots &&
+ + ]
3400 [ + + ]: 33 : ValidateSlotSyncParams(LOG) && SlotSyncWorkerCanRestart())
3401 : 6 : SlotSyncWorkerPMChild = StartChildProcess(B_SLOTSYNC_WORKER);
3402 : :
3403 : : /*
3404 : : * If we need to start a WAL receiver, try to do that now
3405 : : *
3406 : : * Note: if a walreceiver process is already running, it might seem that
3407 : : * we should clear WalReceiverRequested. However, there's a race
3408 : : * condition if the walreceiver terminates and the startup process
3409 : : * immediately requests a new one: it's quite possible to get the signal
3410 : : * for the request before reaping the dead walreceiver process. Better to
3411 : : * risk launching an extra walreceiver than to miss launching one we need.
3412 : : * (The walreceiver code has logic to recognize that it should go away if
3413 : : * not needed.)
3414 : : */
3415 [ + + ]: 155318 : if (WalReceiverRequested)
3416 : : {
3417 [ + + ]: 423 : if (WalReceiverPMChild == NULL &&
3418 [ + + + - ]: 306 : (pmState == PM_STARTUP || pmState == PM_RECOVERY ||
3419 [ + + ]: 305 : pmState == PM_HOT_STANDBY) &&
3420 [ + - ]: 274 : Shutdown <= SmartShutdown)
3421 : : {
3422 : 274 : WalReceiverPMChild = StartChildProcess(B_WAL_RECEIVER);
3423 [ + - ]: 274 : if (WalReceiverPMChild != NULL)
3424 : 274 : WalReceiverRequested = false;
3425 : : /* else leave the flag set, so we'll try again later */
3426 : : }
3427 : : }
3428 : :
3429 : : /* If we need to start a WAL summarizer, try to do that now */
3430 [ + + + + ]: 155318 : if (summarize_wal && WalSummarizerPMChild == NULL &&
3431 [ + + + + ]: 97 : (pmState == PM_RUN || pmState == PM_HOT_STANDBY) &&
3432 [ + - ]: 23 : Shutdown <= SmartShutdown)
3433 : 23 : WalSummarizerPMChild = StartChildProcess(B_WAL_SUMMARIZER);
3434 : :
3435 : : /* Get other worker processes running, if needed */
3436 [ + + + + ]: 155318 : if (StartWorkerNeeded || HaveCrashedWorker)
3437 : 8245 : maybe_start_bgworkers();
3438 : 155318 : }
3439 : :
3440 : : /*
3441 : : * Return string representation of signal.
3442 : : *
3443 : : * Because this is only implemented for signals we already rely on in this
3444 : : * file we don't need to deal with unimplemented or same-numeric-value signals
3445 : : * (as we'd e.g. have to for EWOULDBLOCK / EAGAIN).
3446 : : */
3447 : : static const char *
3448 : 59 : pm_signame(int signal)
3449 : : {
3450 : : #define PM_TOSTR_CASE(sym) case sym: return #sym
3451 [ - - - + : 59 : switch (signal)
- - + - +
- ]
3452 : : {
3453 : 0 : PM_TOSTR_CASE(SIGABRT);
3454 : 0 : PM_TOSTR_CASE(SIGCHLD);
3455 : 0 : PM_TOSTR_CASE(SIGHUP);
3456 : 7 : PM_TOSTR_CASE(SIGINT);
3457 : 0 : PM_TOSTR_CASE(SIGKILL);
3458 : 0 : PM_TOSTR_CASE(SIGQUIT);
3459 : 37 : PM_TOSTR_CASE(SIGTERM);
3460 : 0 : PM_TOSTR_CASE(SIGUSR1);
3461 : 15 : PM_TOSTR_CASE(SIGUSR2);
3462 : 0 : default:
3463 : : /* all signals sent by postmaster should be listed here */
3464 : : Assert(false);
3465 : 0 : return "(unknown)";
3466 : : }
3467 : : #undef PM_TOSTR_CASE
3468 : :
3469 : : return ""; /* silence compiler */
3470 : : }
3471 : :
3472 : : /*
3473 : : * Send a signal to a postmaster child process
3474 : : *
3475 : : * On systems that have setsid(), each child process sets itself up as a
3476 : : * process group leader. For signals that are generally interpreted in the
3477 : : * appropriate fashion, we signal the entire process group not just the
3478 : : * direct child process. This allows us to, for example, SIGQUIT a blocked
3479 : : * archive_recovery script, or SIGINT a script being run by a backend via
3480 : : * system().
3481 : : *
3482 : : * There is a race condition for recently-forked children: they might not
3483 : : * have executed setsid() yet. So we signal the child directly as well as
3484 : : * the group. We assume such a child will handle the signal before trying
3485 : : * to spawn any grandchild processes. We also assume that signaling the
3486 : : * child twice will not cause any problems.
3487 : : */
3488 : : static void
3489 : 11505 : signal_child(PMChild *pmchild, int signal)
3490 : : {
3491 : 11505 : pid_t pid = pmchild->pid;
3492 : :
3493 [ + + ]: 11505 : ereport(DEBUG3,
3494 : : (errmsg_internal("sending signal %d/%s to %s process with pid %d",
3495 : : signal, pm_signame(signal),
3496 : : GetBackendTypeDesc(pmchild->bkend_type),
3497 : : (int) pmchild->pid)));
3498 : :
3499 [ - + ]: 11505 : if (kill(pid, signal) < 0)
3500 [ # # ]: 0 : elog(DEBUG3, "kill(%ld,%d) failed: %m", (long) pid, signal);
3501 : : #ifdef HAVE_SETSID
3502 [ + + ]: 11505 : switch (signal)
3503 : : {
3504 : 6432 : case SIGINT:
3505 : : case SIGTERM:
3506 : : case SIGQUIT:
3507 : : case SIGKILL:
3508 : : case SIGABRT:
3509 [ + + ]: 6432 : if (kill(-pid, signal) < 0)
3510 [ - + ]: 3 : elog(DEBUG3, "kill(%ld,%d) failed: %m", (long) (-pid), signal);
3511 : 6432 : break;
3512 : 5073 : default:
3513 : 5073 : break;
3514 : : }
3515 : : #endif
3516 : 11505 : }
3517 : :
3518 : : /*
3519 : : * Send a signal to the targeted children.
3520 : : */
3521 : : static bool
3522 : 3463 : SignalChildren(int signal, BackendTypeMask targetMask)
3523 : : {
3524 : : dlist_iter iter;
3525 : 3463 : bool signaled = false;
3526 : :
3527 [ + - + + ]: 16713 : dlist_foreach(iter, &ActiveChildList)
3528 : : {
3529 : 13250 : PMChild *bp = dlist_container(PMChild, elem, iter.cur);
3530 : :
3531 : : /*
3532 : : * If we need to distinguish between B_BACKEND and B_WAL_SENDER, check
3533 : : * if any B_BACKEND backends have recently announced that they are
3534 : : * actually WAL senders.
3535 : : */
3536 [ + + ]: 13250 : if (btmask_contains(targetMask, B_WAL_SENDER) != btmask_contains(targetMask, B_BACKEND) &&
3537 [ + + ]: 6978 : bp->bkend_type == B_BACKEND)
3538 : : {
3539 [ + + ]: 577 : if (IsPostmasterChildWalSender(bp->child_slot))
3540 : 48 : bp->bkend_type = B_WAL_SENDER;
3541 : : }
3542 : :
3543 [ + + ]: 13250 : if (!btmask_contains(targetMask, bp->bkend_type))
3544 : 4669 : continue;
3545 : :
3546 : 8581 : signal_child(bp, signal);
3547 : 8581 : signaled = true;
3548 : : }
3549 : 3463 : return signaled;
3550 : : }
3551 : :
3552 : : /*
3553 : : * Send a termination signal to children. This considers all of our children
3554 : : * processes, except syslogger.
3555 : : */
3556 : : static void
3557 : 370 : TerminateChildren(int signal)
3558 : : {
3559 : 370 : SignalChildren(signal, btmask_all_except(B_LOGGER));
3560 [ + + ]: 370 : if (StartupPMChild != NULL)
3561 : : {
3562 [ - + - - : 49 : if (signal == SIGQUIT || signal == SIGKILL || signal == SIGABRT)
- - ]
3563 : 49 : StartupStatus = STARTUP_SIGNALED;
3564 : : }
3565 : 370 : }
3566 : :
3567 : : /*
3568 : : * BackendStartup -- start backend process
3569 : : *
3570 : : * returns: STATUS_ERROR if the fork failed, STATUS_OK otherwise.
3571 : : *
3572 : : * Note: if you change this code, also consider StartAutovacuumWorker and
3573 : : * StartBackgroundWorker.
3574 : : */
3575 : : static int
3576 : 15419 : BackendStartup(ClientSocket *client_sock)
3577 : : {
3578 : 15419 : PMChild *bn = NULL;
3579 : : pid_t pid;
3580 : : BackendStartupData startup_data;
3581 : : CAC_state cac;
3582 : :
3583 : : /*
3584 : : * Capture time that Postmaster got a socket from accept (for logging
3585 : : * connection establishment and setup total duration).
3586 : : */
3587 : 15419 : startup_data.socket_created = GetCurrentTimestamp();
3588 : :
3589 : : /*
3590 : : * Allocate and assign the child slot. Note we must do this before
3591 : : * forking, so that we can handle failures (out of memory or child-process
3592 : : * slots) cleanly.
3593 : : */
3594 : 15419 : cac = canAcceptConnections(B_BACKEND);
3595 [ + + ]: 15419 : if (cac == CAC_OK)
3596 : : {
3597 : : /* Can change later to B_WAL_SENDER */
3598 : 15187 : bn = AssignPostmasterChildSlot(B_BACKEND);
3599 [ + + ]: 15187 : if (!bn)
3600 : : {
3601 : : /*
3602 : : * Too many regular child processes; launch a dead-end child
3603 : : * process instead.
3604 : : */
3605 : 28 : cac = CAC_TOOMANY;
3606 : : }
3607 : : }
3608 [ + + ]: 15419 : if (!bn)
3609 : : {
3610 : 260 : bn = AllocDeadEndChild();
3611 [ - + ]: 260 : if (!bn)
3612 : : {
3613 [ # # ]: 0 : ereport(LOG,
3614 : : (errcode(ERRCODE_OUT_OF_MEMORY),
3615 : : errmsg("out of memory")));
3616 : 0 : return STATUS_ERROR;
3617 : : }
3618 : : }
3619 : :
3620 : : /* Pass down canAcceptConnections state */
3621 : 15419 : startup_data.canAcceptConnections = cac;
3622 : 15419 : bn->rw = NULL;
3623 : :
3624 : : /* Hasn't asked to be notified about any bgworkers yet */
3625 : 15419 : bn->bgworker_notify = false;
3626 : :
3627 : 15419 : pid = postmaster_child_launch(bn->bkend_type, bn->child_slot,
3628 : : &startup_data, sizeof(startup_data),
3629 : : client_sock);
3630 [ - + ]: 15419 : if (pid < 0)
3631 : : {
3632 : : /* in parent, fork failed */
3633 : 0 : int save_errno = errno;
3634 : :
3635 : 0 : (void) ReleasePostmasterChildSlot(bn);
3636 : 0 : errno = save_errno;
3637 [ # # ]: 0 : ereport(LOG,
3638 : : (errmsg("could not fork new process for connection: %m")));
3639 : 0 : report_fork_failure_to_client(client_sock, save_errno);
3640 : 0 : return STATUS_ERROR;
3641 : : }
3642 : :
3643 : : /* in parent, successful fork */
3644 [ + + ]: 15419 : ereport(DEBUG2,
3645 : : (errmsg_internal("forked new %s, pid=%d socket=%d",
3646 : : GetBackendTypeDesc(bn->bkend_type),
3647 : : (int) pid, (int) client_sock->sock)));
3648 : :
3649 : : /*
3650 : : * Everything's been successful, it's safe to add this backend to our list
3651 : : * of backends.
3652 : : */
3653 : 15419 : bn->pid = pid;
3654 : 15419 : return STATUS_OK;
3655 : : }
3656 : :
3657 : : /*
3658 : : * Try to report backend fork() failure to client before we close the
3659 : : * connection. Since we do not care to risk blocking the postmaster on
3660 : : * this connection, we set the connection to non-blocking and try only once.
3661 : : *
3662 : : * This is grungy special-purpose code; we cannot use backend libpq since
3663 : : * it's not up and running.
3664 : : */
3665 : : static void
3666 : 0 : report_fork_failure_to_client(ClientSocket *client_sock, int errnum)
3667 : : {
3668 : : char buffer[1000];
3669 : : int rc;
3670 : :
3671 : : /* Format the error message packet (always V2 protocol) */
3672 : 0 : snprintf(buffer, sizeof(buffer), "E%s%s\n",
3673 : : _("could not fork new process for connection: "),
3674 : : strerror(errnum));
3675 : :
3676 : : /* Set port to non-blocking. Don't do send() if this fails */
3677 [ # # ]: 0 : if (!pg_set_noblock(client_sock->sock))
3678 : 0 : return;
3679 : :
3680 : : /* We'll retry after EINTR, but ignore all other failures */
3681 : : do
3682 : : {
3683 : 0 : rc = send(client_sock->sock, buffer, strlen(buffer) + 1, 0);
3684 [ # # # # ]: 0 : } while (rc < 0 && errno == EINTR);
3685 : : }
3686 : :
3687 : : /*
3688 : : * ExitPostmaster -- cleanup
3689 : : *
3690 : : * Do NOT call exit() directly --- always go through here!
3691 : : */
3692 : : static void
3693 : 1006 : ExitPostmaster(int status)
3694 : : {
3695 : : #ifdef HAVE_PTHREAD_IS_THREADED_NP
3696 : :
3697 : : /*
3698 : : * There is no known cause for a postmaster to become multithreaded after
3699 : : * startup. However, we might reach here via an error exit before
3700 : : * reaching the test in PostmasterMain, so provide the same hint as there.
3701 : : * This message uses LOG level, because an unclean shutdown at this point
3702 : : * would usually not look much different from a clean shutdown.
3703 : : */
3704 : : if (pthread_is_threaded_np() != 0)
3705 : : ereport(LOG,
3706 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3707 : : errmsg("postmaster became multithreaded"),
3708 : : errhint("Set the LC_ALL environment variable to a valid locale.")));
3709 : : #endif
3710 : :
3711 : : /* should cleanup shared memory and kill all backends */
3712 : :
3713 : : /*
3714 : : * Not sure of the semantics here. When the Postmaster dies, should the
3715 : : * backends all be killed? probably not.
3716 : : *
3717 : : * MUST -- vadim 05-10-1999
3718 : : */
3719 : :
3720 : 1006 : proc_exit(status);
3721 : : }
3722 : :
3723 : : /*
3724 : : * Handle pmsignal conditions representing requests from backends,
3725 : : * and check for promote and logrotate requests from pg_ctl.
3726 : : */
3727 : : static void
3728 : 114145 : process_pm_pmsignal(void)
3729 : : {
3730 : 114145 : bool request_state_update = false;
3731 : :
3732 : 114145 : pending_pm_pmsignal = false;
3733 : :
3734 [ + + ]: 114145 : ereport(DEBUG2,
3735 : : (errmsg_internal("postmaster received pmsignal signal")));
3736 : :
3737 : : /*
3738 : : * RECOVERY_STARTED and BEGIN_HOT_STANDBY signals are ignored in
3739 : : * unexpected states. If the startup process quickly starts up, completes
3740 : : * recovery, exits, we might process the death of the startup process
3741 : : * first. We don't want to go back to recovery in that case.
3742 : : */
3743 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_RECOVERY_STARTED) &&
3744 [ + - + - ]: 274 : pmState == PM_STARTUP && Shutdown == NoShutdown)
3745 : : {
3746 : : /* WAL redo has started. We're out of reinitialization. */
3747 : 274 : FatalError = false;
3748 : 274 : AbortStartTime = 0;
3749 : 274 : reachedConsistency = false;
3750 : :
3751 : : /*
3752 : : * Start the archiver if we're responsible for (re-)archiving received
3753 : : * files.
3754 : : */
3755 : : Assert(PgArchPMChild == NULL);
3756 [ + + ]: 274 : if (XLogArchivingAlways())
3757 : 3 : PgArchPMChild = StartChildProcess(B_ARCHIVER);
3758 : :
3759 : : /*
3760 : : * If we aren't planning to enter hot standby mode later, treat
3761 : : * RECOVERY_STARTED as meaning we're out of startup, and report status
3762 : : * accordingly.
3763 : : */
3764 [ + + ]: 274 : if (!EnableHotStandby)
3765 : : {
3766 : 2 : AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_STANDBY);
3767 : : #ifdef USE_SYSTEMD
3768 : : sd_notify(0, "READY=1");
3769 : : #endif
3770 : : }
3771 : :
3772 : 274 : UpdatePMState(PM_RECOVERY);
3773 : : }
3774 : :
3775 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_RECOVERY_CONSISTENT) &&
3776 [ + - + - ]: 183 : pmState == PM_RECOVERY && Shutdown == NoShutdown)
3777 : : {
3778 : 183 : reachedConsistency = true;
3779 : : }
3780 : :
3781 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_BEGIN_HOT_STANDBY) &&
3782 [ + - + - ]: 173 : (pmState == PM_RECOVERY && Shutdown == NoShutdown))
3783 : : {
3784 [ + - ]: 173 : ereport(LOG,
3785 : : (errmsg("database system is ready to accept read-only connections")));
3786 : :
3787 : : /* Report status */
3788 : 173 : AddToDataDirLockFile(LOCK_FILE_LINE_PM_STATUS, PM_STATUS_READY);
3789 : : #ifdef USE_SYSTEMD
3790 : : sd_notify(0, "READY=1");
3791 : : #endif
3792 : :
3793 : 173 : UpdatePMState(PM_HOT_STANDBY);
3794 : 173 : connsAllowed = true;
3795 : :
3796 : : /* Some workers may be scheduled to start now */
3797 : 173 : StartWorkerNeeded = true;
3798 : : }
3799 : :
3800 : : /* Process IO worker start requests. */
3801 : 114145 : if (CheckPostmasterSignal(PMSIGNAL_IO_WORKER_GROW))
3802 : : {
3803 : : /*
3804 : : * No local flag, as the state is exposed through pgaio_worker_*()
3805 : : * functions. This signal is received on potentially actionable level
3806 : : * changes, so that maybe_start_io_workers() will run.
3807 : : */
3808 : : }
3809 : :
3810 : : /* Process background worker state changes. */
3811 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_BACKGROUND_WORKER_CHANGE))
3812 : : {
3813 : : /* Accept new worker requests only if not stopping. */
3814 : 1757 : BackgroundWorkerStateChange(pmState < PM_STOP_BACKENDS);
3815 : 1757 : StartWorkerNeeded = true;
3816 : : }
3817 : :
3818 : : /* Tell syslogger to rotate logfile if requested */
3819 [ + + ]: 114145 : if (SysLoggerPMChild != NULL)
3820 : : {
3821 [ + + ]: 2 : if (CheckLogrotateSignal())
3822 : : {
3823 : 1 : signal_child(SysLoggerPMChild, SIGUSR1);
3824 : 1 : RemoveLogrotateSignalFiles();
3825 : : }
3826 [ - + ]: 1 : else if (CheckPostmasterSignal(PMSIGNAL_ROTATE_LOGFILE))
3827 : : {
3828 : 0 : signal_child(SysLoggerPMChild, SIGUSR1);
3829 : : }
3830 : : }
3831 : :
3832 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER) &&
3833 [ + - + - ]: 108427 : Shutdown <= SmartShutdown && pmState < PM_STOP_BACKENDS)
3834 : : {
3835 : : /*
3836 : : * Start one iteration of the autovacuum daemon, even if autovacuuming
3837 : : * is nominally not enabled. This is so we can have an active defense
3838 : : * against transaction ID wraparound. We set a flag for the main loop
3839 : : * to do it rather than trying to do it here --- this is because the
3840 : : * autovac process itself may send the signal, and we want to handle
3841 : : * that by launching another iteration as soon as the current one
3842 : : * completes.
3843 : : */
3844 : 108427 : start_autovac_launcher = true;
3845 : : }
3846 : :
3847 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_START_AUTOVAC_WORKER) &&
3848 [ + - + - ]: 1575 : Shutdown <= SmartShutdown && pmState < PM_STOP_BACKENDS)
3849 : : {
3850 : : /* The autovacuum launcher wants us to start a worker process. */
3851 : 1575 : StartAutovacuumWorker();
3852 : : }
3853 : :
3854 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_START_WALRECEIVER))
3855 : : {
3856 : : /* Startup Process wants us to start the walreceiver process. */
3857 : 282 : WalReceiverRequested = true;
3858 : : }
3859 : :
3860 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_XLOG_IS_SHUTDOWN))
3861 : : {
3862 : : /* Checkpointer completed the shutdown checkpoint */
3863 [ + - ]: 639 : if (pmState == PM_WAIT_XLOG_SHUTDOWN)
3864 : : {
3865 : : /*
3866 : : * If we have an archiver subprocess, tell it to do a last archive
3867 : : * cycle and quit. Likewise, if we have walsender processes, tell
3868 : : * them to send any remaining WAL and quit.
3869 : : */
3870 : : Assert(Shutdown > NoShutdown);
3871 : :
3872 : : /* Waken archiver for the last time */
3873 [ + + ]: 639 : if (PgArchPMChild != NULL)
3874 : 19 : signal_child(PgArchPMChild, SIGUSR2);
3875 : :
3876 : : /*
3877 : : * Waken walsenders for the last time. No regular backends should
3878 : : * be around anymore.
3879 : : */
3880 : 639 : SignalChildren(SIGUSR2, btmask(B_WAL_SENDER));
3881 : :
3882 : 639 : UpdatePMState(PM_WAIT_XLOG_ARCHIVAL);
3883 : : }
3884 [ # # # # ]: 0 : else if (!FatalError && Shutdown != ImmediateShutdown)
3885 : : {
3886 : : /*
3887 : : * Checkpointer only ought to perform the shutdown checkpoint
3888 : : * during shutdown. If somehow checkpointer did so in another
3889 : : * situation, we have no choice but to crash-restart.
3890 : : *
3891 : : * It's possible however that we get PMSIGNAL_XLOG_IS_SHUTDOWN
3892 : : * outside of PM_WAIT_XLOG_SHUTDOWN if an orderly shutdown was
3893 : : * "interrupted" by a crash or an immediate shutdown.
3894 : : */
3895 [ # # ]: 0 : ereport(LOG,
3896 : : (errmsg("WAL was shut down unexpectedly")));
3897 : :
3898 : : /*
3899 : : * Doesn't seem likely to help to take send_abort_for_crash into
3900 : : * account here.
3901 : : */
3902 : 0 : HandleFatalError(PMQUIT_FOR_CRASH, false);
3903 : : }
3904 : :
3905 : : /*
3906 : : * Need to run PostmasterStateMachine() to check if we already can go
3907 : : * to the next state.
3908 : : */
3909 : 639 : request_state_update = true;
3910 : : }
3911 : :
3912 : : /*
3913 : : * Try to advance postmaster's state machine, if a child requests it.
3914 : : */
3915 [ + + ]: 114145 : if (CheckPostmasterSignal(PMSIGNAL_ADVANCE_STATE_MACHINE))
3916 : : {
3917 : 1394 : request_state_update = true;
3918 : : }
3919 : :
3920 : : /*
3921 : : * Be careful about the order of this action relative to this function's
3922 : : * other actions. Generally, this should be after other actions, in case
3923 : : * they have effects PostmasterStateMachine would need to know about.
3924 : : * However, we should do it before the CheckPromoteSignal step, which
3925 : : * cannot have any (immediate) effect on the state machine, but does
3926 : : * depend on what state we're in now.
3927 : : */
3928 [ + + ]: 114145 : if (request_state_update)
3929 : : {
3930 : 2033 : PostmasterStateMachine();
3931 : : }
3932 : :
3933 [ + + ]: 114145 : if (StartupPMChild != NULL &&
3934 [ + + + + ]: 707 : (pmState == PM_STARTUP || pmState == PM_RECOVERY ||
3935 [ + + + + ]: 1190 : pmState == PM_HOT_STANDBY) &&
3936 : 705 : CheckPromoteSignal())
3937 : : {
3938 : : /*
3939 : : * Tell startup process to finish recovery.
3940 : : *
3941 : : * Leave the promote signal file in place and let the Startup process
3942 : : * do the unlink.
3943 : : */
3944 : 53 : signal_child(StartupPMChild, SIGUSR2);
3945 : : }
3946 : 114145 : }
3947 : :
3948 : : /*
3949 : : * Dummy signal handler
3950 : : *
3951 : : * We use this for signals that we don't actually use in the postmaster,
3952 : : * but we do use in backends. If we were to PG_SIG_IGN such signals in the
3953 : : * postmaster, then a newly started backend might drop a signal that arrives
3954 : : * before it's able to reconfigure its signal processing. (See notes in
3955 : : * tcop/postgres.c.)
3956 : : */
3957 : : static void
3958 : 0 : dummy_handler(SIGNAL_ARGS)
3959 : : {
3960 : 0 : }
3961 : :
3962 : : /*
3963 : : * Count up number of child processes of specified types.
3964 : : */
3965 : : static int
3966 : 7261 : CountChildren(BackendTypeMask targetMask)
3967 : : {
3968 : : dlist_iter iter;
3969 : 7261 : int cnt = 0;
3970 : :
3971 [ + - + + ]: 37014 : dlist_foreach(iter, &ActiveChildList)
3972 : : {
3973 : 29753 : PMChild *bp = dlist_container(PMChild, elem, iter.cur);
3974 : :
3975 : : /*
3976 : : * If we need to distinguish between B_BACKEND and B_WAL_SENDER, check
3977 : : * if any B_BACKEND backends have recently announced that they are
3978 : : * actually WAL senders.
3979 : : */
3980 [ + + ]: 29753 : if (btmask_contains(targetMask, B_WAL_SENDER) != btmask_contains(targetMask, B_BACKEND) &&
3981 [ + + ]: 19640 : bp->bkend_type == B_BACKEND)
3982 : : {
3983 [ - + ]: 945 : if (IsPostmasterChildWalSender(bp->child_slot))
3984 : 0 : bp->bkend_type = B_WAL_SENDER;
3985 : : }
3986 : :
3987 [ + + ]: 29753 : if (!btmask_contains(targetMask, bp->bkend_type))
3988 : 13595 : continue;
3989 : :
3990 [ - + ]: 16158 : ereport(DEBUG4,
3991 : : (errmsg_internal("%s process %d is still running",
3992 : : GetBackendTypeDesc(bp->bkend_type), (int) bp->pid)));
3993 : :
3994 : 16158 : cnt++;
3995 : : }
3996 : 7261 : return cnt;
3997 : : }
3998 : :
3999 : :
4000 : : /*
4001 : : * StartChildProcess -- start an auxiliary process for the postmaster
4002 : : *
4003 : : * "type" determines what kind of child will be started. All child types
4004 : : * initially go to AuxiliaryProcessMain, which will handle common setup.
4005 : : *
4006 : : * Return value of StartChildProcess is subprocess' PMChild entry, or NULL on
4007 : : * failure.
4008 : : */
4009 : : static PMChild *
4010 : 8653 : StartChildProcess(BackendType type)
4011 : : {
4012 : : PMChild *pmchild;
4013 : : pid_t pid;
4014 : :
4015 : 8653 : pmchild = AssignPostmasterChildSlot(type);
4016 [ - + ]: 8653 : if (!pmchild)
4017 : : {
4018 [ # # ]: 0 : if (type == B_AUTOVAC_WORKER)
4019 [ # # ]: 0 : ereport(LOG,
4020 : : (errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
4021 : : errmsg("no slot available for new autovacuum worker process")));
4022 : : else
4023 : : {
4024 : : /* shouldn't happen because we allocate enough slots */
4025 [ # # ]: 0 : elog(LOG, "no postmaster child slot available for aux process");
4026 : : }
4027 : 0 : return NULL;
4028 : : }
4029 : :
4030 : 8653 : pid = postmaster_child_launch(type, pmchild->child_slot, NULL, 0, NULL);
4031 [ - + ]: 8653 : if (pid < 0)
4032 : : {
4033 : : /* in parent, fork failed */
4034 : 0 : ReleasePostmasterChildSlot(pmchild);
4035 [ # # ]: 0 : ereport(LOG,
4036 : : (errmsg("could not fork \"%s\" process: %m", PostmasterChildName(type))));
4037 : :
4038 : : /*
4039 : : * fork failure is fatal during startup, but there's no need to choke
4040 : : * immediately if starting other child types fails.
4041 : : */
4042 [ # # ]: 0 : if (type == B_STARTUP)
4043 : 0 : ExitPostmaster(1);
4044 : 0 : return NULL;
4045 : : }
4046 : :
4047 : : /* in parent, successful fork */
4048 : 8653 : pmchild->pid = pid;
4049 : 8653 : return pmchild;
4050 : : }
4051 : :
4052 : : /*
4053 : : * StartSysLogger -- start the syslogger process
4054 : : */
4055 : : void
4056 : 1 : StartSysLogger(void)
4057 : : {
4058 : : Assert(SysLoggerPMChild == NULL);
4059 : :
4060 : 1 : SysLoggerPMChild = AssignPostmasterChildSlot(B_LOGGER);
4061 [ - + ]: 1 : if (!SysLoggerPMChild)
4062 [ # # ]: 0 : elog(PANIC, "no postmaster child slot available for syslogger");
4063 : 1 : SysLoggerPMChild->pid = SysLogger_Start(SysLoggerPMChild->child_slot);
4064 [ - + ]: 1 : if (SysLoggerPMChild->pid == 0)
4065 : : {
4066 : 0 : ReleasePostmasterChildSlot(SysLoggerPMChild);
4067 : 0 : SysLoggerPMChild = NULL;
4068 : : }
4069 : 1 : }
4070 : :
4071 : : /*
4072 : : * StartAutovacuumWorker
4073 : : * Start an autovac worker process.
4074 : : *
4075 : : * This function is here because it enters the resulting PID into the
4076 : : * postmaster's private backends list.
4077 : : *
4078 : : * NB -- this code very roughly matches BackendStartup.
4079 : : */
4080 : : static void
4081 : 1575 : StartAutovacuumWorker(void)
4082 : : {
4083 : : PMChild *bn;
4084 : :
4085 : : /*
4086 : : * If not in condition to run a process, don't try, but handle it like a
4087 : : * fork failure. This does not normally happen, since the signal is only
4088 : : * supposed to be sent by autovacuum launcher when it's OK to do it, but
4089 : : * we have to check to avoid race-condition problems during DB state
4090 : : * changes.
4091 : : */
4092 [ + - ]: 1575 : if (canAcceptConnections(B_AUTOVAC_WORKER) == CAC_OK)
4093 : : {
4094 : 1575 : bn = StartChildProcess(B_AUTOVAC_WORKER);
4095 [ + - ]: 1575 : if (bn)
4096 : : {
4097 : 1575 : bn->bgworker_notify = false;
4098 : 1575 : bn->rw = NULL;
4099 : 1575 : return;
4100 : : }
4101 : : else
4102 : : {
4103 : : /*
4104 : : * fork failed, fall through to report -- actual error message was
4105 : : * logged by StartChildProcess
4106 : : */
4107 : : }
4108 : : }
4109 : :
4110 : : /*
4111 : : * Report the failure to the launcher, if it's running. (If it's not, we
4112 : : * might not even be connected to shared memory, so don't try to call
4113 : : * AutoVacWorkerFailed.) Note that we also need to signal it so that it
4114 : : * responds to the condition, but we don't do that here, instead waiting
4115 : : * for ServerLoop to do it. This way we avoid a ping-pong signaling in
4116 : : * quick succession between the autovac launcher and postmaster in case
4117 : : * things get ugly.
4118 : : */
4119 [ # # ]: 0 : if (AutoVacLauncherPMChild != NULL)
4120 : : {
4121 : 0 : AutoVacWorkerFailed();
4122 : 0 : avlauncher_needs_signal = true;
4123 : : }
4124 : : }
4125 : :
4126 : :
4127 : : /*
4128 : : * Create the opts file
4129 : : */
4130 : : static bool
4131 : 1004 : CreateOptsFile(int argc, char *argv[], char *fullprogname)
4132 : : {
4133 : : FILE *fp;
4134 : : int i;
4135 : :
4136 : : #define OPTS_FILE "postmaster.opts"
4137 : :
4138 [ - + ]: 1004 : if ((fp = fopen(OPTS_FILE, "w")) == NULL)
4139 : : {
4140 [ # # ]: 0 : ereport(LOG,
4141 : : (errcode_for_file_access(),
4142 : : errmsg("could not create file \"%s\": %m", OPTS_FILE)));
4143 : 0 : return false;
4144 : : }
4145 : :
4146 : 1004 : fprintf(fp, "%s", fullprogname);
4147 [ + + ]: 5231 : for (i = 1; i < argc; i++)
4148 : 4227 : fprintf(fp, " \"%s\"", argv[i]);
4149 : 1004 : fputs("\n", fp);
4150 : :
4151 [ - + ]: 1004 : if (fclose(fp))
4152 : : {
4153 [ # # ]: 0 : ereport(LOG,
4154 : : (errcode_for_file_access(),
4155 : : errmsg("could not write file \"%s\": %m", OPTS_FILE)));
4156 : 0 : return false;
4157 : : }
4158 : :
4159 : 1004 : return true;
4160 : : }
4161 : :
4162 : :
4163 : : /*
4164 : : * Start a new bgworker.
4165 : : * Starting time conditions must have been checked already.
4166 : : *
4167 : : * Returns true on success, false on failure.
4168 : : * In either case, update the RegisteredBgWorker's state appropriately.
4169 : : *
4170 : : * NB -- this code very roughly matches BackendStartup.
4171 : : */
4172 : : static bool
4173 : 3577 : StartBackgroundWorker(RegisteredBgWorker *rw)
4174 : : {
4175 : : PMChild *bn;
4176 : : pid_t worker_pid;
4177 : :
4178 : : Assert(rw->rw_pid == 0);
4179 : :
4180 : : /*
4181 : : * Allocate and assign the child slot. Note we must do this before
4182 : : * forking, so that we can handle failures (out of memory or child-process
4183 : : * slots) cleanly.
4184 : : *
4185 : : * Treat failure as though the worker had crashed. That way, the
4186 : : * postmaster will wait a bit before attempting to start it again; if we
4187 : : * tried again right away, most likely we'd find ourselves hitting the
4188 : : * same resource-exhaustion condition.
4189 : : */
4190 : 3577 : bn = AssignPostmasterChildSlot(B_BG_WORKER);
4191 [ - + ]: 3577 : if (bn == NULL)
4192 : : {
4193 [ # # ]: 0 : ereport(LOG,
4194 : : (errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
4195 : : errmsg("no slot available for new background worker process")));
4196 : 0 : rw->rw_crashed_at = GetCurrentTimestamp();
4197 : 0 : return false;
4198 : : }
4199 : 3577 : bn->rw = rw;
4200 : 3577 : bn->bkend_type = B_BG_WORKER;
4201 : 3577 : bn->bgworker_notify = false;
4202 : :
4203 [ + + ]: 3577 : ereport(DEBUG1,
4204 : : (errmsg_internal("starting background worker process \"%s\"",
4205 : : rw->rw_worker.bgw_name)));
4206 : :
4207 : 3577 : worker_pid = postmaster_child_launch(B_BG_WORKER, bn->child_slot,
4208 : 3577 : &rw->rw_worker, sizeof(BackgroundWorker), NULL);
4209 [ - + ]: 3577 : if (worker_pid == -1)
4210 : : {
4211 : : /* in postmaster, fork failed ... */
4212 [ # # ]: 0 : ereport(LOG,
4213 : : (errmsg("could not fork background worker process: %m")));
4214 : : /* undo what AssignPostmasterChildSlot did */
4215 : 0 : ReleasePostmasterChildSlot(bn);
4216 : :
4217 : : /* mark entry as crashed, so we'll try again later */
4218 : 0 : rw->rw_crashed_at = GetCurrentTimestamp();
4219 : 0 : return false;
4220 : : }
4221 : :
4222 : : /* in postmaster, fork successful ... */
4223 : 3577 : rw->rw_pid = worker_pid;
4224 : 3577 : bn->pid = rw->rw_pid;
4225 : 3577 : ReportBackgroundWorkerPID(rw);
4226 : 3577 : return true;
4227 : : }
4228 : :
4229 : : /*
4230 : : * Does the current postmaster state require starting a worker with the
4231 : : * specified start_time?
4232 : : */
4233 : : static bool
4234 : 4698 : bgworker_should_start_now(BgWorkerStartTime start_time)
4235 : : {
4236 [ - + + + : 4698 : switch (pmState)
- ]
4237 : : {
4238 : 0 : case PM_NO_CHILDREN:
4239 : : case PM_WAIT_CHECKPOINTER:
4240 : : case PM_WAIT_DEAD_END:
4241 : : case PM_WAIT_XLOG_ARCHIVAL:
4242 : : case PM_WAIT_XLOG_SHUTDOWN:
4243 : : case PM_WAIT_IO_WORKERS:
4244 : : case PM_WAIT_BACKENDS:
4245 : : case PM_STOP_BACKENDS:
4246 : 0 : break;
4247 : :
4248 : 3577 : case PM_RUN:
4249 [ + + ]: 3577 : if (start_time == BgWorkerStart_RecoveryFinished)
4250 : 1548 : return true;
4251 : : pg_fallthrough;
4252 : :
4253 : : case PM_HOT_STANDBY:
4254 [ + + ]: 2198 : if (start_time == BgWorkerStart_ConsistentState)
4255 : 2029 : return true;
4256 : : pg_fallthrough;
4257 : :
4258 : : case PM_RECOVERY:
4259 : : case PM_STARTUP:
4260 : : case PM_INIT:
4261 [ - + ]: 1121 : if (start_time == BgWorkerStart_PostmasterStart)
4262 : 0 : return true;
4263 : : }
4264 : :
4265 : 1121 : return false;
4266 : : }
4267 : :
4268 : : /*
4269 : : * If the time is right, start background worker(s).
4270 : : *
4271 : : * As a side effect, the bgworker control variables are set or reset
4272 : : * depending on whether more workers may need to be started.
4273 : : *
4274 : : * We limit the number of workers started per call, to avoid consuming the
4275 : : * postmaster's attention for too long when many such requests are pending.
4276 : : * As long as StartWorkerNeeded is true, ServerLoop will not block and will
4277 : : * call this function again after dealing with any other issues.
4278 : : */
4279 : : static void
4280 : 9249 : maybe_start_bgworkers(void)
4281 : : {
4282 : : #define MAX_BGWORKERS_TO_LAUNCH 100
4283 : 9249 : int num_launched = 0;
4284 : 9249 : TimestampTz now = 0;
4285 : : dlist_mutable_iter iter;
4286 : :
4287 : : /*
4288 : : * During crash recovery, we have no need to be called until the state
4289 : : * transition out of recovery.
4290 : : */
4291 [ - + ]: 9249 : if (FatalError)
4292 : : {
4293 : 0 : StartWorkerNeeded = false;
4294 : 0 : HaveCrashedWorker = false;
4295 : 0 : return;
4296 : : }
4297 : :
4298 : : /* Don't need to be called again unless we find a reason for it below */
4299 : 9249 : StartWorkerNeeded = false;
4300 : 9249 : HaveCrashedWorker = false;
4301 : :
4302 [ + - + + ]: 25326 : dlist_foreach_modify(iter, &BackgroundWorkerList)
4303 : : {
4304 : : RegisteredBgWorker *rw;
4305 : :
4306 : 16077 : rw = dlist_container(RegisteredBgWorker, rw_lnode, iter.cur);
4307 : :
4308 : : /* ignore if already running */
4309 [ + + ]: 16077 : if (rw->rw_pid != 0)
4310 : 8359 : continue;
4311 : :
4312 : : /* if marked for death, clean up and remove from list */
4313 [ - + ]: 7718 : if (rw->rw_terminate)
4314 : : {
4315 : 0 : ForgetBackgroundWorker(rw);
4316 : 0 : continue;
4317 : : }
4318 : :
4319 : : /*
4320 : : * If this worker has crashed previously, maybe it needs to be
4321 : : * restarted (unless on registration it specified it doesn't want to
4322 : : * be restarted at all). Check how long ago did a crash last happen.
4323 : : * If the last crash is too recent, don't start it right away; let it
4324 : : * be restarted once enough time has passed.
4325 : : */
4326 [ + + ]: 7718 : if (rw->rw_crashed_at != 0)
4327 : : {
4328 [ - + ]: 3020 : if (rw->rw_worker.bgw_restart_time == BGW_NEVER_RESTART)
4329 : 0 : {
4330 : : int notify_pid;
4331 : :
4332 : 0 : notify_pid = rw->rw_worker.bgw_notify_pid;
4333 : :
4334 : 0 : ForgetBackgroundWorker(rw);
4335 : :
4336 : : /* Report worker is gone now. */
4337 [ # # ]: 0 : if (notify_pid != 0)
4338 : 0 : kill(notify_pid, SIGUSR1);
4339 : :
4340 : 0 : continue;
4341 : : }
4342 : :
4343 : : /* read system time only when needed */
4344 [ + - ]: 3020 : if (now == 0)
4345 : 3020 : now = GetCurrentTimestamp();
4346 : :
4347 [ + - ]: 3020 : if (!TimestampDifferenceExceeds(rw->rw_crashed_at, now,
4348 : 3020 : rw->rw_worker.bgw_restart_time * 1000))
4349 : : {
4350 : : /* Set flag to remember that we have workers to start later */
4351 : 3020 : HaveCrashedWorker = true;
4352 : 3020 : continue;
4353 : : }
4354 : : }
4355 : :
4356 [ + + ]: 4698 : if (bgworker_should_start_now(rw->rw_worker.bgw_start_time))
4357 : : {
4358 : : /* reset crash time before trying to start worker */
4359 : 3577 : rw->rw_crashed_at = 0;
4360 : :
4361 : : /*
4362 : : * Try to start the worker.
4363 : : *
4364 : : * On failure, give up processing workers for now, but set
4365 : : * StartWorkerNeeded so we'll come back here on the next iteration
4366 : : * of ServerLoop to try again. (We don't want to wait, because
4367 : : * there might be additional ready-to-run workers.) We could set
4368 : : * HaveCrashedWorker as well, since this worker is now marked
4369 : : * crashed, but there's no need because the next run of this
4370 : : * function will do that.
4371 : : */
4372 [ - + ]: 3577 : if (!StartBackgroundWorker(rw))
4373 : : {
4374 : 0 : StartWorkerNeeded = true;
4375 : 0 : return;
4376 : : }
4377 : :
4378 : : /*
4379 : : * If we've launched as many workers as allowed, quit, but have
4380 : : * ServerLoop call us again to look for additional ready-to-run
4381 : : * workers. There might not be any, but we'll find out the next
4382 : : * time we run.
4383 : : */
4384 [ - + ]: 3577 : if (++num_launched >= MAX_BGWORKERS_TO_LAUNCH)
4385 : : {
4386 : 0 : StartWorkerNeeded = true;
4387 : 0 : return;
4388 : : }
4389 : : }
4390 : : }
4391 : : }
4392 : :
4393 : : static bool
4394 : 22632 : maybe_reap_io_worker(int pid)
4395 : : {
4396 [ + + ]: 682540 : for (int i = 0; i < MAX_IO_WORKERS; ++i)
4397 : : {
4398 [ + + ]: 661969 : if (io_worker_children[i] &&
4399 [ + + ]: 44533 : io_worker_children[i]->pid == pid)
4400 : : {
4401 : 2061 : ReleasePostmasterChildSlot(io_worker_children[i]);
4402 : :
4403 : 2061 : --io_worker_count;
4404 : 2061 : io_worker_children[i] = NULL;
4405 : 2061 : return true;
4406 : : }
4407 : : }
4408 : 20571 : return false;
4409 : : }
4410 : :
4411 : : /*
4412 : : * Returns the next time at which maybe_start_io_workers() would start one or
4413 : : * more I/O workers. Any time in the past means ASAP, and 0 means no worker
4414 : : * is currently scheduled.
4415 : : *
4416 : : * This is called by DetermineSleepTime() and also maybe_start_io_workers()
4417 : : * itself, to make sure that they agree.
4418 : : */
4419 : : static TimestampTz
4420 : 315160 : maybe_start_io_workers_scheduled_at(void)
4421 : : {
4422 [ + + ]: 315160 : if (!pgaio_workers_enabled())
4423 : 230 : return 0;
4424 : :
4425 : : /*
4426 : : * If we're in final shutting down state, then we're just waiting for all
4427 : : * processes to exit.
4428 : : */
4429 [ + + ]: 314930 : if (pmState >= PM_WAIT_IO_WORKERS)
4430 : 5334 : return 0;
4431 : :
4432 : : /* Don't start new workers during an immediate shutdown either. */
4433 [ + + ]: 309596 : if (Shutdown >= ImmediateShutdown)
4434 : 2320 : return 0;
4435 : :
4436 : : /*
4437 : : * Don't start new workers if we're in the shutdown phase of a crash
4438 : : * restart. But we *do* need to start if we're already starting up again.
4439 : : */
4440 [ + + + + ]: 307276 : if (FatalError && pmState >= PM_STOP_BACKENDS)
4441 : 134 : return 0;
4442 : :
4443 : : /*
4444 : : * Don't start a worker if we're at or above the maximum. (Excess workers
4445 : : * exit when the GUC is lowered, but the count can be temporarily too high
4446 : : * until they are reaped.)
4447 : : */
4448 [ + + ]: 307142 : if (io_worker_count >= io_max_workers)
4449 : 88 : return 0;
4450 : :
4451 : : /* If we're under the minimum, start a worker as soon as possible. */
4452 [ + + ]: 307054 : if (io_worker_count < io_min_workers)
4453 : 2050 : return TIMESTAMP_MINUS_INFINITY; /* start worker ASAP */
4454 : :
4455 : : /* Only proceed if a "grow" signal has been received from a worker. */
4456 [ + + ]: 305004 : if (!pgaio_worker_pm_test_grow_signal_sent())
4457 : 304902 : return 0;
4458 : :
4459 : : /*
4460 : : * maybe_start_io_workers() should start a new I/O worker after this time,
4461 : : * or as soon as possible if is already in the past.
4462 : : */
4463 : 102 : return io_worker_launch_next_time;
4464 : : }
4465 : :
4466 : : /*
4467 : : * Start I/O workers if required. Used at startup, to respond to change of
4468 : : * the io_min_workers GUC, when asked to start a new one due to submission
4469 : : * queue backlog, and after workers terminate in response to errors (by
4470 : : * starting "replacement" workers).
4471 : : */
4472 : : static void
4473 : 158388 : maybe_start_io_workers(void)
4474 : : {
4475 : : TimestampTz scheduled_at;
4476 : :
4477 [ + + ]: 160449 : while ((scheduled_at = maybe_start_io_workers_scheduled_at()) != 0)
4478 : : {
4479 : 2128 : TimestampTz now = GetCurrentTimestamp();
4480 : : PMChild *child;
4481 : : int i;
4482 : :
4483 : : Assert(pmState < PM_WAIT_IO_WORKERS);
4484 : :
4485 : : /* Still waiting for the scheduled time? */
4486 [ + + ]: 2128 : if (scheduled_at > now)
4487 : 24 : break;
4488 : :
4489 : : /*
4490 : : * Compute next launch time relative to the previous value, so that
4491 : : * time spent on the postmaster's other duties don't result in an
4492 : : * inaccurate launch interval.
4493 : : */
4494 : 2104 : io_worker_launch_next_time =
4495 : 2104 : TimestampTzPlusMilliseconds(io_worker_launch_next_time,
4496 : : io_worker_launch_interval);
4497 : :
4498 : : /*
4499 : : * If that's already in the past, the interval is either impossibly
4500 : : * short or we received no requests for new workers for a period.
4501 : : * Compute a new future time relative to now instead.
4502 : : */
4503 [ + + ]: 2104 : if (io_worker_launch_next_time <= now)
4504 : 1081 : io_worker_launch_next_time =
4505 : 1081 : TimestampTzPlusMilliseconds(now, io_worker_launch_interval);
4506 : :
4507 : : /*
4508 : : * Check if a grow signal has been received, but the grow request has
4509 : : * been canceled since then because work ran out. We've still
4510 : : * advanced the next launch time, to suppress repeat signals from
4511 : : * workers until then.
4512 : : */
4513 [ + + + + ]: 2104 : if (io_worker_count >= io_min_workers && !pgaio_worker_pm_test_grow())
4514 : : {
4515 : 43 : pgaio_worker_pm_clear_grow_signal_sent();
4516 : 43 : break;
4517 : : }
4518 : :
4519 : : /* find unused entry in io_worker_children array */
4520 [ + - ]: 3697 : for (i = 0; i < MAX_IO_WORKERS; ++i)
4521 : : {
4522 [ + + ]: 3697 : if (io_worker_children[i] == NULL)
4523 : 2061 : break;
4524 : : }
4525 [ - + ]: 2061 : if (i == MAX_IO_WORKERS)
4526 [ # # ]: 0 : elog(ERROR, "could not find a free IO worker slot");
4527 : :
4528 : : /* Try to launch one. */
4529 : 2061 : child = StartChildProcess(B_IO_WORKER);
4530 [ + - ]: 2061 : if (child != NULL)
4531 : : {
4532 : 2061 : io_worker_children[i] = child;
4533 : 2061 : ++io_worker_count;
4534 : : }
4535 : : else
4536 : : {
4537 : : /*
4538 : : * Fork failure: we'll try again after the launch interval
4539 : : * expires, or be called again without delay if we don't yet have
4540 : : * io_min_workers. Don't loop here though, the postmaster has
4541 : : * other duties.
4542 : : */
4543 : 0 : break;
4544 : : }
4545 : : }
4546 : :
4547 : : /*
4548 : : * Workers decide when to shut down by themselves, according to the
4549 : : * io_max_workers and io_worker_idle_timeout GUCs.
4550 : : */
4551 : 158388 : }
4552 : :
4553 : :
4554 : : /*
4555 : : * When a backend asks to be notified about worker state changes, we
4556 : : * set a flag in its backend entry. The background worker machinery needs
4557 : : * to know when such backends exit.
4558 : : */
4559 : : bool
4560 : 2740 : PostmasterMarkPIDForWorkerNotify(int pid)
4561 : : {
4562 : : dlist_iter iter;
4563 : : PMChild *bp;
4564 : :
4565 [ + - + - ]: 7094 : dlist_foreach(iter, &ActiveChildList)
4566 : : {
4567 : 7094 : bp = dlist_container(PMChild, elem, iter.cur);
4568 [ + + ]: 7094 : if (bp->pid == pid)
4569 : : {
4570 : 2740 : bp->bgworker_notify = true;
4571 : 2740 : return true;
4572 : : }
4573 : : }
4574 : 0 : return false;
4575 : : }
4576 : :
4577 : : #ifdef WIN32
4578 : :
4579 : : /*
4580 : : * Subset implementation of waitpid() for Windows. We assume pid is -1
4581 : : * (that is, check all child processes) and options is WNOHANG (don't wait).
4582 : : */
4583 : : static pid_t
4584 : : waitpid(pid_t pid, int *exitstatus, int options)
4585 : : {
4586 : : win32_deadchild_waitinfo *childinfo;
4587 : : DWORD exitcode;
4588 : : DWORD dwd;
4589 : : ULONG_PTR key;
4590 : : OVERLAPPED *ovl;
4591 : :
4592 : : /* Try to consume one win32_deadchild_waitinfo from the queue. */
4593 : : if (!GetQueuedCompletionStatus(win32ChildQueue, &dwd, &key, &ovl, 0))
4594 : : {
4595 : : errno = EAGAIN;
4596 : : return -1;
4597 : : }
4598 : :
4599 : : childinfo = (win32_deadchild_waitinfo *) key;
4600 : : pid = childinfo->procId;
4601 : :
4602 : : /*
4603 : : * Remove handle from wait - required even though it's set to wait only
4604 : : * once
4605 : : */
4606 : : UnregisterWaitEx(childinfo->waitHandle, NULL);
4607 : :
4608 : : if (!GetExitCodeProcess(childinfo->procHandle, &exitcode))
4609 : : {
4610 : : /*
4611 : : * Should never happen. Inform user and set a fixed exitcode.
4612 : : */
4613 : : write_stderr("could not read exit code for process\n");
4614 : : exitcode = 255;
4615 : : }
4616 : : *exitstatus = exitcode;
4617 : :
4618 : : /*
4619 : : * Close the process handle. Only after this point can the PID can be
4620 : : * recycled by the kernel.
4621 : : */
4622 : : CloseHandle(childinfo->procHandle);
4623 : :
4624 : : /*
4625 : : * Free struct that was allocated before the call to
4626 : : * RegisterWaitForSingleObject()
4627 : : */
4628 : : pfree(childinfo);
4629 : :
4630 : : return pid;
4631 : : }
4632 : :
4633 : : /*
4634 : : * Note! Code below executes on a thread pool! All operations must
4635 : : * be thread safe! Note that elog() and friends must *not* be used.
4636 : : */
4637 : : static void WINAPI
4638 : : pgwin32_deadchild_callback(PVOID lpParameter, BOOLEAN TimerOrWaitFired)
4639 : : {
4640 : : /* Should never happen, since we use INFINITE as timeout value. */
4641 : : if (TimerOrWaitFired)
4642 : : return;
4643 : :
4644 : : /*
4645 : : * Post the win32_deadchild_waitinfo object for waitpid() to deal with. If
4646 : : * that fails, we leak the object, but we also leak a whole process and
4647 : : * get into an unrecoverable state, so there's not much point in worrying
4648 : : * about that. We'd like to panic, but we can't use that infrastructure
4649 : : * from this thread.
4650 : : */
4651 : : if (!PostQueuedCompletionStatus(win32ChildQueue,
4652 : : 0,
4653 : : (ULONG_PTR) lpParameter,
4654 : : NULL))
4655 : : write_stderr("could not post child completion status\n");
4656 : :
4657 : : /* Queue SIGCHLD signal. */
4658 : : pg_queue_signal(SIGCHLD);
4659 : : }
4660 : :
4661 : : /*
4662 : : * Queue a waiter to signal when this child dies. The wait will be handled
4663 : : * automatically by an operating system thread pool. The memory and the
4664 : : * process handle will be freed by a later call to waitpid().
4665 : : */
4666 : : void
4667 : : pgwin32_register_deadchild_callback(HANDLE procHandle, DWORD procId)
4668 : : {
4669 : : win32_deadchild_waitinfo *childinfo;
4670 : :
4671 : : childinfo = palloc_object(win32_deadchild_waitinfo);
4672 : : childinfo->procHandle = procHandle;
4673 : : childinfo->procId = procId;
4674 : :
4675 : : if (!RegisterWaitForSingleObject(&childinfo->waitHandle,
4676 : : procHandle,
4677 : : pgwin32_deadchild_callback,
4678 : : childinfo,
4679 : : INFINITE,
4680 : : WT_EXECUTEONLYONCE | WT_EXECUTEINWAITTHREAD))
4681 : : ereport(FATAL,
4682 : : (errmsg_internal("could not register process for wait: error code %lu",
4683 : : GetLastError())));
4684 : : }
4685 : :
4686 : : #endif /* WIN32 */
4687 : :
4688 : : /*
4689 : : * Initialize one and only handle for monitoring postmaster death.
4690 : : *
4691 : : * Called once in the postmaster, so that child processes can subsequently
4692 : : * monitor if their parent is dead.
4693 : : */
4694 : : static void
4695 : 1004 : InitPostmasterDeathWatchHandle(void)
4696 : : {
4697 : : #ifndef WIN32
4698 : :
4699 : : /*
4700 : : * Create a pipe. Postmaster holds the write end of the pipe open
4701 : : * (POSTMASTER_FD_OWN), and children hold the read end. Children can pass
4702 : : * the read file descriptor to select() to wake up in case postmaster
4703 : : * dies, or check for postmaster death with a (read() == 0). Children must
4704 : : * close the write end as soon as possible after forking, because EOF
4705 : : * won't be signaled in the read end until all processes have closed the
4706 : : * write fd. That is taken care of in ClosePostmasterPorts().
4707 : : */
4708 : : Assert(MyProcPid == PostmasterPid);
4709 [ - + ]: 1004 : if (pipe(postmaster_alive_fds) < 0)
4710 [ # # ]: 0 : ereport(FATAL,
4711 : : (errcode_for_file_access(),
4712 : : errmsg_internal("could not create pipe to monitor postmaster death: %m")));
4713 : :
4714 : : /* Notify fd.c that we've eaten two FDs for the pipe. */
4715 : 1004 : ReserveExternalFD();
4716 : 1004 : ReserveExternalFD();
4717 : :
4718 : : /*
4719 : : * Set O_NONBLOCK to allow testing for the fd's presence with a read()
4720 : : * call.
4721 : : */
4722 [ - + ]: 1004 : if (fcntl(postmaster_alive_fds[POSTMASTER_FD_WATCH], F_SETFL, O_NONBLOCK) == -1)
4723 [ # # ]: 0 : ereport(FATAL,
4724 : : (errcode_for_socket_access(),
4725 : : errmsg_internal("could not set postmaster death monitoring pipe to nonblocking mode: %m")));
4726 : : #else
4727 : :
4728 : : /*
4729 : : * On Windows, we use a process handle for the same purpose.
4730 : : */
4731 : : if (DuplicateHandle(GetCurrentProcess(),
4732 : : GetCurrentProcess(),
4733 : : GetCurrentProcess(),
4734 : : &PostmasterHandle,
4735 : : 0,
4736 : : TRUE,
4737 : : DUPLICATE_SAME_ACCESS) == 0)
4738 : : ereport(FATAL,
4739 : : (errmsg_internal("could not duplicate postmaster handle: error code %lu",
4740 : : GetLastError())));
4741 : : #endif /* WIN32 */
4742 : 1004 : }
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