Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * nbtree.c
4 : * Implementation of Lehman and Yao's btree management algorithm for
5 : * Postgres.
6 : *
7 : * NOTES
8 : * This file contains only the public interface routines.
9 : *
10 : *
11 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
12 : * Portions Copyright (c) 1994, Regents of the University of California
13 : *
14 : * IDENTIFICATION
15 : * src/backend/access/nbtree/nbtree.c
16 : *
17 : *-------------------------------------------------------------------------
18 : */
19 : #include "postgres.h"
20 :
21 : #include "access/nbtree.h"
22 : #include "access/relscan.h"
23 : #include "access/stratnum.h"
24 : #include "commands/progress.h"
25 : #include "commands/vacuum.h"
26 : #include "nodes/execnodes.h"
27 : #include "pgstat.h"
28 : #include "storage/bulk_write.h"
29 : #include "storage/condition_variable.h"
30 : #include "storage/indexfsm.h"
31 : #include "storage/ipc.h"
32 : #include "storage/lmgr.h"
33 : #include "storage/read_stream.h"
34 : #include "utils/datum.h"
35 : #include "utils/fmgrprotos.h"
36 : #include "utils/index_selfuncs.h"
37 : #include "utils/memutils.h"
38 :
39 :
40 : /*
41 : * BTPARALLEL_NOT_INITIALIZED indicates that the scan has not started.
42 : *
43 : * BTPARALLEL_NEED_PRIMSCAN indicates that some process must now seize the
44 : * scan to advance it via another call to _bt_first.
45 : *
46 : * BTPARALLEL_ADVANCING indicates that some process is advancing the scan to
47 : * a new page; others must wait.
48 : *
49 : * BTPARALLEL_IDLE indicates that no backend is currently advancing the scan
50 : * to a new page; some process can start doing that.
51 : *
52 : * BTPARALLEL_DONE indicates that the scan is complete (including error exit).
53 : */
54 : typedef enum
55 : {
56 : BTPARALLEL_NOT_INITIALIZED,
57 : BTPARALLEL_NEED_PRIMSCAN,
58 : BTPARALLEL_ADVANCING,
59 : BTPARALLEL_IDLE,
60 : BTPARALLEL_DONE,
61 : } BTPS_State;
62 :
63 : /*
64 : * BTParallelScanDescData contains btree specific shared information required
65 : * for parallel scan.
66 : */
67 : typedef struct BTParallelScanDescData
68 : {
69 : BlockNumber btps_nextScanPage; /* next page to be scanned */
70 : BlockNumber btps_lastCurrPage; /* page whose sibling link was copied into
71 : * btps_nextScanPage */
72 : BTPS_State btps_pageStatus; /* indicates whether next page is
73 : * available for scan. see above for
74 : * possible states of parallel scan. */
75 : LWLock btps_lock; /* protects shared parallel state */
76 : ConditionVariable btps_cv; /* used to synchronize parallel scan */
77 :
78 : /*
79 : * btps_arrElems is used when scans need to schedule another primitive
80 : * index scan with one or more SAOP arrays. Holds BTArrayKeyInfo.cur_elem
81 : * offsets for each = scan key associated with a ScalarArrayOp array.
82 : */
83 : int btps_arrElems[FLEXIBLE_ARRAY_MEMBER];
84 :
85 : /*
86 : * Additional space (at the end of the struct) is used when scans need to
87 : * schedule another primitive index scan with one or more skip arrays.
88 : * Holds a flattened datum representation for each = scan key associated
89 : * with a skip array.
90 : */
91 : } BTParallelScanDescData;
92 :
93 : typedef struct BTParallelScanDescData *BTParallelScanDesc;
94 :
95 :
96 : static void _bt_parallel_serialize_arrays(Relation rel, BTParallelScanDesc btscan,
97 : BTScanOpaque so);
98 : static void _bt_parallel_restore_arrays(Relation rel, BTParallelScanDesc btscan,
99 : BTScanOpaque so);
100 : static void btvacuumscan(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
101 : IndexBulkDeleteCallback callback, void *callback_state,
102 : BTCycleId cycleid);
103 : static BlockNumber btvacuumpage(BTVacState *vstate, Buffer buf);
104 : static BTVacuumPosting btreevacuumposting(BTVacState *vstate,
105 : IndexTuple posting,
106 : OffsetNumber updatedoffset,
107 : int *nremaining);
108 :
109 :
110 : /*
111 : * Btree handler function: return IndexAmRoutine with access method parameters
112 : * and callbacks.
113 : */
114 : Datum
115 3284628 : bthandler(PG_FUNCTION_ARGS)
116 : {
117 3284628 : IndexAmRoutine *amroutine = makeNode(IndexAmRoutine);
118 :
119 3284628 : amroutine->amstrategies = BTMaxStrategyNumber;
120 3284628 : amroutine->amsupport = BTNProcs;
121 3284628 : amroutine->amoptsprocnum = BTOPTIONS_PROC;
122 3284628 : amroutine->amcanorder = true;
123 3284628 : amroutine->amcanorderbyop = false;
124 3284628 : amroutine->amcanhash = false;
125 3284628 : amroutine->amconsistentequality = true;
126 3284628 : amroutine->amconsistentordering = true;
127 3284628 : amroutine->amcanbackward = true;
128 3284628 : amroutine->amcanunique = true;
129 3284628 : amroutine->amcanmulticol = true;
130 3284628 : amroutine->amoptionalkey = true;
131 3284628 : amroutine->amsearcharray = true;
132 3284628 : amroutine->amsearchnulls = true;
133 3284628 : amroutine->amstorage = false;
134 3284628 : amroutine->amclusterable = true;
135 3284628 : amroutine->ampredlocks = true;
136 3284628 : amroutine->amcanparallel = true;
137 3284628 : amroutine->amcanbuildparallel = true;
138 3284628 : amroutine->amcaninclude = true;
139 3284628 : amroutine->amusemaintenanceworkmem = false;
140 3284628 : amroutine->amsummarizing = false;
141 3284628 : amroutine->amparallelvacuumoptions =
142 : VACUUM_OPTION_PARALLEL_BULKDEL | VACUUM_OPTION_PARALLEL_COND_CLEANUP;
143 3284628 : amroutine->amkeytype = InvalidOid;
144 :
145 3284628 : amroutine->ambuild = btbuild;
146 3284628 : amroutine->ambuildempty = btbuildempty;
147 3284628 : amroutine->aminsert = btinsert;
148 3284628 : amroutine->aminsertcleanup = NULL;
149 3284628 : amroutine->ambulkdelete = btbulkdelete;
150 3284628 : amroutine->amvacuumcleanup = btvacuumcleanup;
151 3284628 : amroutine->amcanreturn = btcanreturn;
152 3284628 : amroutine->amcostestimate = btcostestimate;
153 3284628 : amroutine->amgettreeheight = btgettreeheight;
154 3284628 : amroutine->amoptions = btoptions;
155 3284628 : amroutine->amproperty = btproperty;
156 3284628 : amroutine->ambuildphasename = btbuildphasename;
157 3284628 : amroutine->amvalidate = btvalidate;
158 3284628 : amroutine->amadjustmembers = btadjustmembers;
159 3284628 : amroutine->ambeginscan = btbeginscan;
160 3284628 : amroutine->amrescan = btrescan;
161 3284628 : amroutine->amgettuple = btgettuple;
162 3284628 : amroutine->amgetbitmap = btgetbitmap;
163 3284628 : amroutine->amendscan = btendscan;
164 3284628 : amroutine->ammarkpos = btmarkpos;
165 3284628 : amroutine->amrestrpos = btrestrpos;
166 3284628 : amroutine->amestimateparallelscan = btestimateparallelscan;
167 3284628 : amroutine->aminitparallelscan = btinitparallelscan;
168 3284628 : amroutine->amparallelrescan = btparallelrescan;
169 3284628 : amroutine->amtranslatestrategy = bttranslatestrategy;
170 3284628 : amroutine->amtranslatecmptype = bttranslatecmptype;
171 :
172 3284628 : PG_RETURN_POINTER(amroutine);
173 : }
174 :
175 : /*
176 : * btbuildempty() -- build an empty btree index in the initialization fork
177 : */
178 : void
179 164 : btbuildempty(Relation index)
180 : {
181 164 : bool allequalimage = _bt_allequalimage(index, false);
182 : BulkWriteState *bulkstate;
183 : BulkWriteBuffer metabuf;
184 :
185 164 : bulkstate = smgr_bulk_start_rel(index, INIT_FORKNUM);
186 :
187 : /* Construct metapage. */
188 164 : metabuf = smgr_bulk_get_buf(bulkstate);
189 164 : _bt_initmetapage((Page) metabuf, P_NONE, 0, allequalimage);
190 164 : smgr_bulk_write(bulkstate, BTREE_METAPAGE, metabuf, true);
191 :
192 164 : smgr_bulk_finish(bulkstate);
193 164 : }
194 :
195 : /*
196 : * btinsert() -- insert an index tuple into a btree.
197 : *
198 : * Descend the tree recursively, find the appropriate location for our
199 : * new tuple, and put it there.
200 : */
201 : bool
202 7264292 : btinsert(Relation rel, Datum *values, bool *isnull,
203 : ItemPointer ht_ctid, Relation heapRel,
204 : IndexUniqueCheck checkUnique,
205 : bool indexUnchanged,
206 : IndexInfo *indexInfo)
207 : {
208 : bool result;
209 : IndexTuple itup;
210 :
211 : /* generate an index tuple */
212 7264292 : itup = index_form_tuple(RelationGetDescr(rel), values, isnull);
213 7264292 : itup->t_tid = *ht_ctid;
214 :
215 7264292 : result = _bt_doinsert(rel, itup, checkUnique, indexUnchanged, heapRel);
216 :
217 7263780 : pfree(itup);
218 :
219 7263780 : return result;
220 : }
221 :
222 : /*
223 : * btgettuple() -- Get the next tuple in the scan.
224 : */
225 : bool
226 35650960 : btgettuple(IndexScanDesc scan, ScanDirection dir)
227 : {
228 35650960 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
229 : bool res;
230 :
231 : Assert(scan->heapRelation != NULL);
232 :
233 : /* btree indexes are never lossy */
234 35650960 : scan->xs_recheck = false;
235 :
236 : /* Each loop iteration performs another primitive index scan */
237 : do
238 : {
239 : /*
240 : * If we've already initialized this scan, we can just advance it in
241 : * the appropriate direction. If we haven't done so yet, we call
242 : * _bt_first() to get the first item in the scan.
243 : */
244 35667872 : if (!BTScanPosIsValid(so->currPos))
245 15973326 : res = _bt_first(scan, dir);
246 : else
247 : {
248 : /*
249 : * Check to see if we should kill the previously-fetched tuple.
250 : */
251 19694546 : if (scan->kill_prior_tuple)
252 : {
253 : /*
254 : * Yes, remember it for later. (We'll deal with all such
255 : * tuples at once right before leaving the index page.) The
256 : * test for numKilled overrun is not just paranoia: if the
257 : * caller reverses direction in the indexscan then the same
258 : * item might get entered multiple times. It's not worth
259 : * trying to optimize that, so we don't detect it, but instead
260 : * just forget any excess entries.
261 : */
262 487092 : if (so->killedItems == NULL)
263 171652 : so->killedItems = (int *)
264 171652 : palloc(MaxTIDsPerBTreePage * sizeof(int));
265 487092 : if (so->numKilled < MaxTIDsPerBTreePage)
266 487092 : so->killedItems[so->numKilled++] = so->currPos.itemIndex;
267 : }
268 :
269 : /*
270 : * Now continue the scan.
271 : */
272 19694546 : res = _bt_next(scan, dir);
273 : }
274 :
275 : /* If we have a tuple, return it ... */
276 35667872 : if (res)
277 28613888 : break;
278 : /* ... otherwise see if we need another primitive index scan */
279 7053984 : } while (so->numArrayKeys && _bt_start_prim_scan(scan, dir));
280 :
281 35650960 : return res;
282 : }
283 :
284 : /*
285 : * btgetbitmap() -- gets all matching tuples, and adds them to a bitmap
286 : */
287 : int64
288 13066 : btgetbitmap(IndexScanDesc scan, TIDBitmap *tbm)
289 : {
290 13066 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
291 13066 : int64 ntids = 0;
292 : ItemPointer heapTid;
293 :
294 : Assert(scan->heapRelation == NULL);
295 :
296 : /* Each loop iteration performs another primitive index scan */
297 : do
298 : {
299 : /* Fetch the first page & tuple */
300 13696 : if (_bt_first(scan, ForwardScanDirection))
301 : {
302 : /* Save tuple ID, and continue scanning */
303 9766 : heapTid = &scan->xs_heaptid;
304 9766 : tbm_add_tuples(tbm, heapTid, 1, false);
305 9766 : ntids++;
306 :
307 : for (;;)
308 : {
309 : /*
310 : * Advance to next tuple within page. This is the same as the
311 : * easy case in _bt_next().
312 : */
313 1998632 : if (++so->currPos.itemIndex > so->currPos.lastItem)
314 : {
315 : /* let _bt_next do the heavy lifting */
316 15272 : if (!_bt_next(scan, ForwardScanDirection))
317 9766 : break;
318 : }
319 :
320 : /* Save tuple ID, and continue scanning */
321 1988866 : heapTid = &so->currPos.items[so->currPos.itemIndex].heapTid;
322 1988866 : tbm_add_tuples(tbm, heapTid, 1, false);
323 1988866 : ntids++;
324 : }
325 : }
326 : /* Now see if we need another primitive index scan */
327 13696 : } while (so->numArrayKeys && _bt_start_prim_scan(scan, ForwardScanDirection));
328 :
329 13066 : return ntids;
330 : }
331 :
332 : /*
333 : * btbeginscan() -- start a scan on a btree index
334 : */
335 : IndexScanDesc
336 15293766 : btbeginscan(Relation rel, int nkeys, int norderbys)
337 : {
338 : IndexScanDesc scan;
339 : BTScanOpaque so;
340 :
341 : /* no order by operators allowed */
342 : Assert(norderbys == 0);
343 :
344 : /* get the scan */
345 15293766 : scan = RelationGetIndexScan(rel, nkeys, norderbys);
346 :
347 : /* allocate private workspace */
348 15293766 : so = (BTScanOpaque) palloc(sizeof(BTScanOpaqueData));
349 15293766 : BTScanPosInvalidate(so->currPos);
350 15293766 : BTScanPosInvalidate(so->markPos);
351 15293766 : if (scan->numberOfKeys > 0)
352 15280488 : so->keyData = (ScanKey) palloc(scan->numberOfKeys * sizeof(ScanKeyData));
353 : else
354 13278 : so->keyData = NULL;
355 :
356 15293766 : so->skipScan = false;
357 15293766 : so->needPrimScan = false;
358 15293766 : so->scanBehind = false;
359 15293766 : so->oppositeDirCheck = false;
360 15293766 : so->arrayKeys = NULL;
361 15293766 : so->orderProcs = NULL;
362 15293766 : so->arrayContext = NULL;
363 :
364 15293766 : so->killedItems = NULL; /* until needed */
365 15293766 : so->numKilled = 0;
366 :
367 : /*
368 : * We don't know yet whether the scan will be index-only, so we do not
369 : * allocate the tuple workspace arrays until btrescan. However, we set up
370 : * scan->xs_itupdesc whether we'll need it or not, since that's so cheap.
371 : */
372 15293766 : so->currTuples = so->markTuples = NULL;
373 :
374 15293766 : scan->xs_itupdesc = RelationGetDescr(rel);
375 :
376 15293766 : scan->opaque = so;
377 :
378 15293766 : return scan;
379 : }
380 :
381 : /*
382 : * btrescan() -- rescan an index relation
383 : */
384 : void
385 15970754 : btrescan(IndexScanDesc scan, ScanKey scankey, int nscankeys,
386 : ScanKey orderbys, int norderbys)
387 : {
388 15970754 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
389 :
390 : /* we aren't holding any read locks, but gotta drop the pins */
391 15970754 : if (BTScanPosIsValid(so->currPos))
392 : {
393 : /* Before leaving current page, deal with any killed items */
394 71620 : if (so->numKilled > 0)
395 1006 : _bt_killitems(scan);
396 71620 : BTScanPosUnpinIfPinned(so->currPos);
397 71620 : BTScanPosInvalidate(so->currPos);
398 : }
399 :
400 : /*
401 : * We prefer to eagerly drop leaf page pins before btgettuple returns.
402 : * This avoids making VACUUM wait to acquire a cleanup lock on the page.
403 : *
404 : * We cannot safely drop leaf page pins during index-only scans due to a
405 : * race condition involving VACUUM setting pages all-visible in the VM.
406 : * It's also unsafe for plain index scans that use a non-MVCC snapshot.
407 : *
408 : * When we drop pins eagerly, the mechanism that marks so->killedItems[]
409 : * index tuples LP_DEAD has to deal with concurrent TID recycling races.
410 : * The scheme used to detect unsafe TID recycling won't work when scanning
411 : * unlogged relations (since it involves saving an affected page's LSN).
412 : * Opt out of eager pin dropping during unlogged relation scans for now
413 : * (this is preferable to opting out of kill_prior_tuple LP_DEAD setting).
414 : *
415 : * Also opt out of dropping leaf page pins eagerly during bitmap scans.
416 : * Pins cannot be held for more than an instant during bitmap scans either
417 : * way, so we might as well avoid wasting cycles on acquiring page LSNs.
418 : *
419 : * See nbtree/README section on making concurrent TID recycling safe.
420 : *
421 : * Note: so->dropPin should never change across rescans.
422 : */
423 47566362 : so->dropPin = (!scan->xs_want_itup &&
424 15624854 : IsMVCCSnapshot(scan->xs_snapshot) &&
425 46030246 : RelationNeedsWAL(scan->indexRelation) &&
426 14434638 : scan->heapRelation != NULL);
427 :
428 15970754 : so->markItemIndex = -1;
429 15970754 : so->needPrimScan = false;
430 15970754 : so->scanBehind = false;
431 15970754 : so->oppositeDirCheck = false;
432 15970754 : BTScanPosUnpinIfPinned(so->markPos);
433 15970754 : BTScanPosInvalidate(so->markPos);
434 :
435 : /*
436 : * Allocate tuple workspace arrays, if needed for an index-only scan and
437 : * not already done in a previous rescan call. To save on palloc
438 : * overhead, both workspaces are allocated as one palloc block; only this
439 : * function and btendscan know that.
440 : *
441 : * NOTE: this data structure also makes it safe to return data from a
442 : * "name" column, even though btree name_ops uses an underlying storage
443 : * datatype of cstring. The risk there is that "name" is supposed to be
444 : * padded to NAMEDATALEN, but the actual index tuple is probably shorter.
445 : * However, since we only return data out of tuples sitting in the
446 : * currTuples array, a fetch of NAMEDATALEN bytes can at worst pull some
447 : * data out of the markTuples array --- running off the end of memory for
448 : * a SIGSEGV is not possible. Yeah, this is ugly as sin, but it beats
449 : * adding special-case treatment for name_ops elsewhere.
450 : */
451 15970754 : if (scan->xs_want_itup && so->currTuples == NULL)
452 : {
453 135502 : so->currTuples = (char *) palloc(BLCKSZ * 2);
454 135502 : so->markTuples = so->currTuples + BLCKSZ;
455 : }
456 :
457 : /*
458 : * Reset the scan keys
459 : */
460 15970754 : if (scankey && scan->numberOfKeys > 0)
461 15957282 : memcpy(scan->keyData, scankey, scan->numberOfKeys * sizeof(ScanKeyData));
462 15970754 : so->numberOfKeys = 0; /* until _bt_preprocess_keys sets it */
463 15970754 : so->numArrayKeys = 0; /* ditto */
464 15970754 : }
465 :
466 : /*
467 : * btendscan() -- close down a scan
468 : */
469 : void
470 15292200 : btendscan(IndexScanDesc scan)
471 : {
472 15292200 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
473 :
474 : /* we aren't holding any read locks, but gotta drop the pins */
475 15292200 : if (BTScanPosIsValid(so->currPos))
476 : {
477 : /* Before leaving current page, deal with any killed items */
478 8846612 : if (so->numKilled > 0)
479 93178 : _bt_killitems(scan);
480 8846612 : BTScanPosUnpinIfPinned(so->currPos);
481 : }
482 :
483 15292200 : so->markItemIndex = -1;
484 15292200 : BTScanPosUnpinIfPinned(so->markPos);
485 :
486 : /* No need to invalidate positions, the RAM is about to be freed. */
487 :
488 : /* Release storage */
489 15292200 : if (so->keyData != NULL)
490 15278952 : pfree(so->keyData);
491 : /* so->arrayKeys and so->orderProcs are in arrayContext */
492 15292200 : if (so->arrayContext != NULL)
493 4494 : MemoryContextDelete(so->arrayContext);
494 15292200 : if (so->killedItems != NULL)
495 171586 : pfree(so->killedItems);
496 15292200 : if (so->currTuples != NULL)
497 135458 : pfree(so->currTuples);
498 : /* so->markTuples should not be pfree'd, see btrescan */
499 15292200 : pfree(so);
500 15292200 : }
501 :
502 : /*
503 : * btmarkpos() -- save current scan position
504 : */
505 : void
506 130138 : btmarkpos(IndexScanDesc scan)
507 : {
508 130138 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
509 :
510 : /* There may be an old mark with a pin (but no lock). */
511 130138 : BTScanPosUnpinIfPinned(so->markPos);
512 :
513 : /*
514 : * Just record the current itemIndex. If we later step to next page
515 : * before releasing the marked position, _bt_steppage makes a full copy of
516 : * the currPos struct in markPos. If (as often happens) the mark is moved
517 : * before we leave the page, we don't have to do that work.
518 : */
519 130138 : if (BTScanPosIsValid(so->currPos))
520 130138 : so->markItemIndex = so->currPos.itemIndex;
521 : else
522 : {
523 0 : BTScanPosInvalidate(so->markPos);
524 0 : so->markItemIndex = -1;
525 : }
526 130138 : }
527 :
528 : /*
529 : * btrestrpos() -- restore scan to last saved position
530 : */
531 : void
532 54066 : btrestrpos(IndexScanDesc scan)
533 : {
534 54066 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
535 :
536 54066 : if (so->markItemIndex >= 0)
537 : {
538 : /*
539 : * The scan has never moved to a new page since the last mark. Just
540 : * restore the itemIndex.
541 : *
542 : * NB: In this case we can't count on anything in so->markPos to be
543 : * accurate.
544 : */
545 53958 : so->currPos.itemIndex = so->markItemIndex;
546 : }
547 : else
548 : {
549 : /*
550 : * The scan moved to a new page after last mark or restore, and we are
551 : * now restoring to the marked page. We aren't holding any read
552 : * locks, but if we're still holding the pin for the current position,
553 : * we must drop it.
554 : */
555 108 : if (BTScanPosIsValid(so->currPos))
556 : {
557 : /* Before leaving current page, deal with any killed items */
558 108 : if (so->numKilled > 0)
559 0 : _bt_killitems(scan);
560 108 : BTScanPosUnpinIfPinned(so->currPos);
561 : }
562 :
563 108 : if (BTScanPosIsValid(so->markPos))
564 : {
565 : /* bump pin on mark buffer for assignment to current buffer */
566 108 : if (BTScanPosIsPinned(so->markPos))
567 0 : IncrBufferRefCount(so->markPos.buf);
568 108 : memcpy(&so->currPos, &so->markPos,
569 : offsetof(BTScanPosData, items[1]) +
570 108 : so->markPos.lastItem * sizeof(BTScanPosItem));
571 108 : if (so->currTuples)
572 0 : memcpy(so->currTuples, so->markTuples,
573 0 : so->markPos.nextTupleOffset);
574 : /* Reset the scan's array keys (see _bt_steppage for why) */
575 108 : if (so->numArrayKeys)
576 : {
577 0 : _bt_start_array_keys(scan, so->currPos.dir);
578 0 : so->needPrimScan = false;
579 : }
580 : }
581 : else
582 0 : BTScanPosInvalidate(so->currPos);
583 : }
584 54066 : }
585 :
586 : /*
587 : * btestimateparallelscan -- estimate storage for BTParallelScanDescData
588 : */
589 : Size
590 64 : btestimateparallelscan(Relation rel, int nkeys, int norderbys)
591 : {
592 64 : int16 nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel);
593 : Size estnbtreeshared,
594 : genericattrspace;
595 :
596 : /*
597 : * Pessimistically assume that every input scan key will be output with
598 : * its own SAOP array
599 : */
600 64 : estnbtreeshared = offsetof(BTParallelScanDescData, btps_arrElems) +
601 : sizeof(int) * nkeys;
602 :
603 : /* Single column indexes cannot possibly use a skip array */
604 64 : if (nkeyatts == 1)
605 46 : return estnbtreeshared;
606 :
607 : /*
608 : * Pessimistically assume that all attributes prior to the least
609 : * significant attribute require a skip array (and an associated key)
610 : */
611 18 : genericattrspace = datumEstimateSpace((Datum) 0, false, true,
612 : sizeof(Datum));
613 36 : for (int attnum = 1; attnum < nkeyatts; attnum++)
614 : {
615 : CompactAttribute *attr;
616 :
617 : /*
618 : * We make the conservative assumption that every index column will
619 : * also require a skip array.
620 : *
621 : * Every skip array must have space to store its scan key's sk_flags.
622 : */
623 18 : estnbtreeshared = add_size(estnbtreeshared, sizeof(int));
624 :
625 : /* Consider space required to store a datum of opclass input type */
626 18 : attr = TupleDescCompactAttr(rel->rd_att, attnum - 1);
627 18 : if (attr->attbyval)
628 18 : {
629 : /* This index attribute stores pass-by-value datums */
630 18 : Size estfixed = datumEstimateSpace((Datum) 0, false,
631 18 : true, attr->attlen);
632 :
633 18 : estnbtreeshared = add_size(estnbtreeshared, estfixed);
634 18 : continue;
635 : }
636 :
637 : /*
638 : * This index attribute stores pass-by-reference datums.
639 : *
640 : * Assume that serializing this array will use just as much space as a
641 : * pass-by-value datum, in addition to space for the largest possible
642 : * whole index tuple (this is not just a per-datum portion of the
643 : * largest possible tuple because that'd be almost as large anyway).
644 : *
645 : * This is quite conservative, but it's not clear how we could do much
646 : * better. The executor requires an up-front storage request size
647 : * that reliably covers the scan's high watermark memory usage. We
648 : * can't be sure of the real high watermark until the scan is over.
649 : */
650 0 : estnbtreeshared = add_size(estnbtreeshared, genericattrspace);
651 0 : estnbtreeshared = add_size(estnbtreeshared, BTMaxItemSize);
652 : }
653 :
654 18 : return estnbtreeshared;
655 : }
656 :
657 : /*
658 : * _bt_parallel_serialize_arrays() -- Serialize parallel array state.
659 : *
660 : * Caller must have exclusively locked btscan->btps_lock when called.
661 : */
662 : static void
663 36 : _bt_parallel_serialize_arrays(Relation rel, BTParallelScanDesc btscan,
664 : BTScanOpaque so)
665 : {
666 : char *datumshared;
667 :
668 : /* Space for serialized datums begins immediately after btps_arrElems[] */
669 36 : datumshared = ((char *) &btscan->btps_arrElems[so->numArrayKeys]);
670 72 : for (int i = 0; i < so->numArrayKeys; i++)
671 : {
672 36 : BTArrayKeyInfo *array = &so->arrayKeys[i];
673 36 : ScanKey skey = &so->keyData[array->scan_key];
674 :
675 36 : if (array->num_elems != -1)
676 : {
677 : /* Save SAOP array's cur_elem (no need to copy key/datum) */
678 : Assert(!(skey->sk_flags & SK_BT_SKIP));
679 36 : btscan->btps_arrElems[i] = array->cur_elem;
680 36 : continue;
681 : }
682 :
683 : /* Save all mutable state associated with skip array's key */
684 : Assert(skey->sk_flags & SK_BT_SKIP);
685 0 : memcpy(datumshared, &skey->sk_flags, sizeof(int));
686 0 : datumshared += sizeof(int);
687 :
688 0 : if (skey->sk_flags & (SK_BT_MINVAL | SK_BT_MAXVAL))
689 : {
690 : /* No sk_argument datum to serialize */
691 : Assert(skey->sk_argument == 0);
692 0 : continue;
693 : }
694 :
695 0 : datumSerialize(skey->sk_argument, (skey->sk_flags & SK_ISNULL) != 0,
696 0 : array->attbyval, array->attlen, &datumshared);
697 : }
698 36 : }
699 :
700 : /*
701 : * _bt_parallel_restore_arrays() -- Restore serialized parallel array state.
702 : *
703 : * Caller must have exclusively locked btscan->btps_lock when called.
704 : */
705 : static void
706 36 : _bt_parallel_restore_arrays(Relation rel, BTParallelScanDesc btscan,
707 : BTScanOpaque so)
708 : {
709 : char *datumshared;
710 :
711 : /* Space for serialized datums begins immediately after btps_arrElems[] */
712 36 : datumshared = ((char *) &btscan->btps_arrElems[so->numArrayKeys]);
713 72 : for (int i = 0; i < so->numArrayKeys; i++)
714 : {
715 36 : BTArrayKeyInfo *array = &so->arrayKeys[i];
716 36 : ScanKey skey = &so->keyData[array->scan_key];
717 : bool isnull;
718 :
719 36 : if (array->num_elems != -1)
720 : {
721 : /* Restore SAOP array using its saved cur_elem */
722 : Assert(!(skey->sk_flags & SK_BT_SKIP));
723 36 : array->cur_elem = btscan->btps_arrElems[i];
724 36 : skey->sk_argument = array->elem_values[array->cur_elem];
725 36 : continue;
726 : }
727 :
728 : /* Restore skip array by restoring its key directly */
729 0 : if (!array->attbyval && skey->sk_argument)
730 0 : pfree(DatumGetPointer(skey->sk_argument));
731 0 : skey->sk_argument = (Datum) 0;
732 0 : memcpy(&skey->sk_flags, datumshared, sizeof(int));
733 0 : datumshared += sizeof(int);
734 :
735 : Assert(skey->sk_flags & SK_BT_SKIP);
736 :
737 0 : if (skey->sk_flags & (SK_BT_MINVAL | SK_BT_MAXVAL))
738 : {
739 : /* No sk_argument datum to restore */
740 0 : continue;
741 : }
742 :
743 0 : skey->sk_argument = datumRestore(&datumshared, &isnull);
744 0 : if (isnull)
745 : {
746 : Assert(skey->sk_argument == 0);
747 : Assert(skey->sk_flags & SK_SEARCHNULL);
748 : Assert(skey->sk_flags & SK_ISNULL);
749 : }
750 : }
751 36 : }
752 :
753 : /*
754 : * btinitparallelscan -- initialize BTParallelScanDesc for parallel btree scan
755 : */
756 : void
757 64 : btinitparallelscan(void *target)
758 : {
759 64 : BTParallelScanDesc bt_target = (BTParallelScanDesc) target;
760 :
761 64 : LWLockInitialize(&bt_target->btps_lock,
762 : LWTRANCHE_PARALLEL_BTREE_SCAN);
763 64 : bt_target->btps_nextScanPage = InvalidBlockNumber;
764 64 : bt_target->btps_lastCurrPage = InvalidBlockNumber;
765 64 : bt_target->btps_pageStatus = BTPARALLEL_NOT_INITIALIZED;
766 64 : ConditionVariableInit(&bt_target->btps_cv);
767 64 : }
768 :
769 : /*
770 : * btparallelrescan() -- reset parallel scan
771 : */
772 : void
773 24 : btparallelrescan(IndexScanDesc scan)
774 : {
775 : BTParallelScanDesc btscan;
776 24 : ParallelIndexScanDesc parallel_scan = scan->parallel_scan;
777 :
778 : Assert(parallel_scan);
779 :
780 24 : btscan = (BTParallelScanDesc) OffsetToPointer(parallel_scan,
781 : parallel_scan->ps_offset_am);
782 :
783 : /*
784 : * In theory, we don't need to acquire the LWLock here, because there
785 : * shouldn't be any other workers running at this point, but we do so for
786 : * consistency.
787 : */
788 24 : LWLockAcquire(&btscan->btps_lock, LW_EXCLUSIVE);
789 24 : btscan->btps_nextScanPage = InvalidBlockNumber;
790 24 : btscan->btps_lastCurrPage = InvalidBlockNumber;
791 24 : btscan->btps_pageStatus = BTPARALLEL_NOT_INITIALIZED;
792 24 : LWLockRelease(&btscan->btps_lock);
793 24 : }
794 :
795 : /*
796 : * _bt_parallel_seize() -- Begin the process of advancing the scan to a new
797 : * page. Other scans must wait until we call _bt_parallel_release()
798 : * or _bt_parallel_done().
799 : *
800 : * The return value is true if we successfully seized the scan and false
801 : * if we did not. The latter case occurs when no pages remain, or when
802 : * another primitive index scan is scheduled that caller's backend cannot
803 : * start just yet (only backends that call from _bt_first are capable of
804 : * starting primitive index scans, which they indicate by passing first=true).
805 : *
806 : * If the return value is true, *next_scan_page returns the next page of the
807 : * scan, and *last_curr_page returns the page that *next_scan_page came from.
808 : * An invalid *next_scan_page means the scan hasn't yet started, or that
809 : * caller needs to start the next primitive index scan (if it's the latter
810 : * case we'll set so.needPrimScan).
811 : *
812 : * Callers should ignore the value of *next_scan_page and *last_curr_page if
813 : * the return value is false.
814 : */
815 : bool
816 1658 : _bt_parallel_seize(IndexScanDesc scan, BlockNumber *next_scan_page,
817 : BlockNumber *last_curr_page, bool first)
818 : {
819 1658 : Relation rel = scan->indexRelation;
820 1658 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
821 1658 : bool exit_loop = false,
822 1658 : status = true,
823 1658 : endscan = false;
824 1658 : ParallelIndexScanDesc parallel_scan = scan->parallel_scan;
825 : BTParallelScanDesc btscan;
826 :
827 1658 : *next_scan_page = InvalidBlockNumber;
828 1658 : *last_curr_page = InvalidBlockNumber;
829 :
830 : /*
831 : * Reset so->currPos, and initialize moreLeft/moreRight such that the next
832 : * call to _bt_readnextpage treats this backend similarly to a serial
833 : * backend that steps from *last_curr_page to *next_scan_page (unless this
834 : * backend's so->currPos is initialized by _bt_readfirstpage before then).
835 : */
836 1658 : BTScanPosInvalidate(so->currPos);
837 1658 : so->currPos.moreLeft = so->currPos.moreRight = true;
838 :
839 1658 : if (first)
840 : {
841 : /*
842 : * Initialize array related state when called from _bt_first, assuming
843 : * that this will be the first primitive index scan for the scan
844 : */
845 446 : so->needPrimScan = false;
846 446 : so->scanBehind = false;
847 446 : so->oppositeDirCheck = false;
848 : }
849 : else
850 : {
851 : /*
852 : * Don't attempt to seize the scan when it requires another primitive
853 : * index scan, since caller's backend cannot start it right now
854 : */
855 1212 : if (so->needPrimScan)
856 0 : return false;
857 : }
858 :
859 1658 : btscan = (BTParallelScanDesc) OffsetToPointer(parallel_scan,
860 : parallel_scan->ps_offset_am);
861 :
862 : while (1)
863 : {
864 1686 : LWLockAcquire(&btscan->btps_lock, LW_EXCLUSIVE);
865 :
866 1686 : if (btscan->btps_pageStatus == BTPARALLEL_DONE)
867 : {
868 : /* We're done with this parallel index scan */
869 306 : status = false;
870 : }
871 1380 : else if (btscan->btps_pageStatus == BTPARALLEL_IDLE &&
872 1228 : btscan->btps_nextScanPage == P_NONE)
873 : {
874 : /* End this parallel index scan */
875 16 : status = false;
876 16 : endscan = true;
877 : }
878 1364 : else if (btscan->btps_pageStatus == BTPARALLEL_NEED_PRIMSCAN)
879 : {
880 : Assert(so->numArrayKeys);
881 :
882 36 : if (first)
883 : {
884 : /* Can start scheduled primitive scan right away, so do so */
885 36 : btscan->btps_pageStatus = BTPARALLEL_ADVANCING;
886 :
887 : /* Restore scan's array keys from serialized values */
888 36 : _bt_parallel_restore_arrays(rel, btscan, so);
889 36 : exit_loop = true;
890 : }
891 : else
892 : {
893 : /*
894 : * Don't attempt to seize the scan when it requires another
895 : * primitive index scan, since caller's backend cannot start
896 : * it right now
897 : */
898 0 : status = false;
899 : }
900 :
901 : /*
902 : * Either way, update backend local state to indicate that a
903 : * pending primitive scan is required
904 : */
905 36 : so->needPrimScan = true;
906 36 : so->scanBehind = false;
907 36 : so->oppositeDirCheck = false;
908 : }
909 1328 : else if (btscan->btps_pageStatus != BTPARALLEL_ADVANCING)
910 : {
911 : /*
912 : * We have successfully seized control of the scan for the purpose
913 : * of advancing it to a new page!
914 : */
915 1300 : btscan->btps_pageStatus = BTPARALLEL_ADVANCING;
916 : Assert(btscan->btps_nextScanPage != P_NONE);
917 1300 : *next_scan_page = btscan->btps_nextScanPage;
918 1300 : *last_curr_page = btscan->btps_lastCurrPage;
919 1300 : exit_loop = true;
920 : }
921 1686 : LWLockRelease(&btscan->btps_lock);
922 1686 : if (exit_loop || !status)
923 : break;
924 28 : ConditionVariableSleep(&btscan->btps_cv, WAIT_EVENT_BTREE_PAGE);
925 : }
926 1658 : ConditionVariableCancelSleep();
927 :
928 : /* When the scan has reached the rightmost (or leftmost) page, end it */
929 1658 : if (endscan)
930 16 : _bt_parallel_done(scan);
931 :
932 1658 : return status;
933 : }
934 :
935 : /*
936 : * _bt_parallel_release() -- Complete the process of advancing the scan to a
937 : * new page. We now have the new value btps_nextScanPage; another backend
938 : * can now begin advancing the scan.
939 : *
940 : * Callers whose scan uses array keys must save their curr_page argument so
941 : * that it can be passed to _bt_parallel_primscan_schedule, should caller
942 : * determine that another primitive index scan is required.
943 : *
944 : * If caller's next_scan_page is P_NONE, the scan has reached the index's
945 : * rightmost/leftmost page. This is treated as reaching the end of the scan
946 : * within _bt_parallel_seize.
947 : *
948 : * Note: unlike the serial case, parallel scans don't need to remember both
949 : * sibling links. next_scan_page is whichever link is next given the scan's
950 : * direction. That's all we'll ever need, since the direction of a parallel
951 : * scan can never change.
952 : */
953 : void
954 1336 : _bt_parallel_release(IndexScanDesc scan, BlockNumber next_scan_page,
955 : BlockNumber curr_page)
956 : {
957 1336 : ParallelIndexScanDesc parallel_scan = scan->parallel_scan;
958 : BTParallelScanDesc btscan;
959 :
960 : Assert(BlockNumberIsValid(next_scan_page));
961 :
962 1336 : btscan = (BTParallelScanDesc) OffsetToPointer(parallel_scan,
963 : parallel_scan->ps_offset_am);
964 :
965 1336 : LWLockAcquire(&btscan->btps_lock, LW_EXCLUSIVE);
966 1336 : btscan->btps_nextScanPage = next_scan_page;
967 1336 : btscan->btps_lastCurrPage = curr_page;
968 1336 : btscan->btps_pageStatus = BTPARALLEL_IDLE;
969 1336 : LWLockRelease(&btscan->btps_lock);
970 1336 : ConditionVariableSignal(&btscan->btps_cv);
971 1336 : }
972 :
973 : /*
974 : * _bt_parallel_done() -- Mark the parallel scan as complete.
975 : *
976 : * When there are no pages left to scan, this function should be called to
977 : * notify other workers. Otherwise, they might wait forever for the scan to
978 : * advance to the next page.
979 : */
980 : void
981 7067404 : _bt_parallel_done(IndexScanDesc scan)
982 : {
983 7067404 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
984 7067404 : ParallelIndexScanDesc parallel_scan = scan->parallel_scan;
985 : BTParallelScanDesc btscan;
986 7067404 : bool status_changed = false;
987 :
988 : Assert(!BTScanPosIsValid(so->currPos));
989 :
990 : /* Do nothing, for non-parallel scans */
991 7067404 : if (parallel_scan == NULL)
992 7067240 : return;
993 :
994 : /*
995 : * Should not mark parallel scan done when there's still a pending
996 : * primitive index scan
997 : */
998 164 : if (so->needPrimScan)
999 36 : return;
1000 :
1001 128 : btscan = (BTParallelScanDesc) OffsetToPointer(parallel_scan,
1002 : parallel_scan->ps_offset_am);
1003 :
1004 : /*
1005 : * Mark the parallel scan as done, unless some other process did so
1006 : * already
1007 : */
1008 128 : LWLockAcquire(&btscan->btps_lock, LW_EXCLUSIVE);
1009 : Assert(btscan->btps_pageStatus != BTPARALLEL_NEED_PRIMSCAN);
1010 128 : if (btscan->btps_pageStatus != BTPARALLEL_DONE)
1011 : {
1012 88 : btscan->btps_pageStatus = BTPARALLEL_DONE;
1013 88 : status_changed = true;
1014 : }
1015 128 : LWLockRelease(&btscan->btps_lock);
1016 :
1017 : /* wake up all the workers associated with this parallel scan */
1018 128 : if (status_changed)
1019 88 : ConditionVariableBroadcast(&btscan->btps_cv);
1020 : }
1021 :
1022 : /*
1023 : * _bt_parallel_primscan_schedule() -- Schedule another primitive index scan.
1024 : *
1025 : * Caller passes the curr_page most recently passed to _bt_parallel_release
1026 : * by its backend. Caller successfully schedules the next primitive index scan
1027 : * if the shared parallel state hasn't been seized since caller's backend last
1028 : * advanced the scan.
1029 : */
1030 : void
1031 36 : _bt_parallel_primscan_schedule(IndexScanDesc scan, BlockNumber curr_page)
1032 : {
1033 36 : Relation rel = scan->indexRelation;
1034 36 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
1035 36 : ParallelIndexScanDesc parallel_scan = scan->parallel_scan;
1036 : BTParallelScanDesc btscan;
1037 :
1038 : Assert(so->numArrayKeys);
1039 :
1040 36 : btscan = (BTParallelScanDesc) OffsetToPointer(parallel_scan,
1041 : parallel_scan->ps_offset_am);
1042 :
1043 36 : LWLockAcquire(&btscan->btps_lock, LW_EXCLUSIVE);
1044 36 : if (btscan->btps_lastCurrPage == curr_page &&
1045 36 : btscan->btps_pageStatus == BTPARALLEL_IDLE)
1046 : {
1047 36 : btscan->btps_nextScanPage = InvalidBlockNumber;
1048 36 : btscan->btps_lastCurrPage = InvalidBlockNumber;
1049 36 : btscan->btps_pageStatus = BTPARALLEL_NEED_PRIMSCAN;
1050 :
1051 : /* Serialize scan's current array keys */
1052 36 : _bt_parallel_serialize_arrays(rel, btscan, so);
1053 : }
1054 36 : LWLockRelease(&btscan->btps_lock);
1055 36 : }
1056 :
1057 : /*
1058 : * Bulk deletion of all index entries pointing to a set of heap tuples.
1059 : * The set of target tuples is specified via a callback routine that tells
1060 : * whether any given heap tuple (identified by ItemPointer) is being deleted.
1061 : *
1062 : * Result: a palloc'd struct containing statistical info for VACUUM displays.
1063 : */
1064 : IndexBulkDeleteResult *
1065 2850 : btbulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
1066 : IndexBulkDeleteCallback callback, void *callback_state)
1067 : {
1068 2850 : Relation rel = info->index;
1069 : BTCycleId cycleid;
1070 :
1071 : /* allocate stats if first time through, else re-use existing struct */
1072 2850 : if (stats == NULL)
1073 2846 : stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
1074 :
1075 : /* Establish the vacuum cycle ID to use for this scan */
1076 : /* The ENSURE stuff ensures we clean up shared memory on failure */
1077 2850 : PG_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel));
1078 : {
1079 2850 : cycleid = _bt_start_vacuum(rel);
1080 :
1081 2850 : btvacuumscan(info, stats, callback, callback_state, cycleid);
1082 : }
1083 2850 : PG_END_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel));
1084 2850 : _bt_end_vacuum(rel);
1085 :
1086 2850 : return stats;
1087 : }
1088 :
1089 : /*
1090 : * Post-VACUUM cleanup.
1091 : *
1092 : * Result: a palloc'd struct containing statistical info for VACUUM displays.
1093 : */
1094 : IndexBulkDeleteResult *
1095 227742 : btvacuumcleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *stats)
1096 : {
1097 : BlockNumber num_delpages;
1098 :
1099 : /* No-op in ANALYZE ONLY mode */
1100 227742 : if (info->analyze_only)
1101 17622 : return stats;
1102 :
1103 : /*
1104 : * If btbulkdelete was called, we need not do anything (we just maintain
1105 : * the information used within _bt_vacuum_needs_cleanup() by calling
1106 : * _bt_set_cleanup_info() below).
1107 : *
1108 : * If btbulkdelete was _not_ called, then we have a choice to make: we
1109 : * must decide whether or not a btvacuumscan() call is needed now (i.e.
1110 : * whether the ongoing VACUUM operation can entirely avoid a physical scan
1111 : * of the index). A call to _bt_vacuum_needs_cleanup() decides it for us
1112 : * now.
1113 : */
1114 210120 : if (stats == NULL)
1115 : {
1116 : /* Check if VACUUM operation can entirely avoid btvacuumscan() call */
1117 207870 : if (!_bt_vacuum_needs_cleanup(info->index))
1118 207860 : return NULL;
1119 :
1120 : /*
1121 : * Since we aren't going to actually delete any leaf items, there's no
1122 : * need to go through all the vacuum-cycle-ID pushups here.
1123 : *
1124 : * Posting list tuples are a source of inaccuracy for cleanup-only
1125 : * scans. btvacuumscan() will assume that the number of index tuples
1126 : * from each page can be used as num_index_tuples, even though
1127 : * num_index_tuples is supposed to represent the number of TIDs in the
1128 : * index. This naive approach can underestimate the number of tuples
1129 : * in the index significantly.
1130 : *
1131 : * We handle the problem by making num_index_tuples an estimate in
1132 : * cleanup-only case.
1133 : */
1134 10 : stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
1135 10 : btvacuumscan(info, stats, NULL, NULL, 0);
1136 10 : stats->estimated_count = true;
1137 : }
1138 :
1139 : /*
1140 : * Maintain num_delpages value in metapage for _bt_vacuum_needs_cleanup().
1141 : *
1142 : * num_delpages is the number of deleted pages now in the index that were
1143 : * not safe to place in the FSM to be recycled just yet. num_delpages is
1144 : * greater than 0 only when _bt_pagedel() actually deleted pages during
1145 : * our call to btvacuumscan(). Even then, _bt_pendingfsm_finalize() must
1146 : * have failed to place any newly deleted pages in the FSM just moments
1147 : * ago. (Actually, there are edge cases where recycling of the current
1148 : * VACUUM's newly deleted pages does not even become safe by the time the
1149 : * next VACUUM comes around. See nbtree/README.)
1150 : */
1151 : Assert(stats->pages_deleted >= stats->pages_free);
1152 2260 : num_delpages = stats->pages_deleted - stats->pages_free;
1153 2260 : _bt_set_cleanup_info(info->index, num_delpages);
1154 :
1155 : /*
1156 : * It's quite possible for us to be fooled by concurrent page splits into
1157 : * double-counting some index tuples, so disbelieve any total that exceeds
1158 : * the underlying heap's count ... if we know that accurately. Otherwise
1159 : * this might just make matters worse.
1160 : */
1161 2260 : if (!info->estimated_count)
1162 : {
1163 2192 : if (stats->num_index_tuples > info->num_heap_tuples)
1164 38 : stats->num_index_tuples = info->num_heap_tuples;
1165 : }
1166 :
1167 2260 : return stats;
1168 : }
1169 :
1170 : /*
1171 : * btvacuumscan --- scan the index for VACUUMing purposes
1172 : *
1173 : * This combines the functions of looking for leaf tuples that are deletable
1174 : * according to the vacuum callback, looking for empty pages that can be
1175 : * deleted, and looking for old deleted pages that can be recycled. Both
1176 : * btbulkdelete and btvacuumcleanup invoke this (the latter only if no
1177 : * btbulkdelete call occurred and _bt_vacuum_needs_cleanup returned true).
1178 : *
1179 : * The caller is responsible for initially allocating/zeroing a stats struct
1180 : * and for obtaining a vacuum cycle ID if necessary.
1181 : */
1182 : static void
1183 2860 : btvacuumscan(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
1184 : IndexBulkDeleteCallback callback, void *callback_state,
1185 : BTCycleId cycleid)
1186 : {
1187 2860 : Relation rel = info->index;
1188 : BTVacState vstate;
1189 : BlockNumber num_pages;
1190 : bool needLock;
1191 : BlockRangeReadStreamPrivate p;
1192 2860 : ReadStream *stream = NULL;
1193 :
1194 : /*
1195 : * Reset fields that track information about the entire index now. This
1196 : * avoids double-counting in the case where a single VACUUM command
1197 : * requires multiple scans of the index.
1198 : *
1199 : * Avoid resetting the tuples_removed and pages_newly_deleted fields here,
1200 : * since they track information about the VACUUM command, and so must last
1201 : * across each call to btvacuumscan().
1202 : *
1203 : * (Note that pages_free is treated as state about the whole index, not
1204 : * the current VACUUM. This is appropriate because RecordFreeIndexPage()
1205 : * calls are idempotent, and get repeated for the same deleted pages in
1206 : * some scenarios. The point for us is to track the number of recyclable
1207 : * pages in the index at the end of the VACUUM command.)
1208 : */
1209 2860 : stats->num_pages = 0;
1210 2860 : stats->num_index_tuples = 0;
1211 2860 : stats->pages_deleted = 0;
1212 2860 : stats->pages_free = 0;
1213 :
1214 : /* Set up info to pass down to btvacuumpage */
1215 2860 : vstate.info = info;
1216 2860 : vstate.stats = stats;
1217 2860 : vstate.callback = callback;
1218 2860 : vstate.callback_state = callback_state;
1219 2860 : vstate.cycleid = cycleid;
1220 :
1221 : /* Create a temporary memory context to run _bt_pagedel in */
1222 2860 : vstate.pagedelcontext = AllocSetContextCreate(CurrentMemoryContext,
1223 : "_bt_pagedel",
1224 : ALLOCSET_DEFAULT_SIZES);
1225 :
1226 : /* Initialize vstate fields used by _bt_pendingfsm_finalize */
1227 2860 : vstate.bufsize = 0;
1228 2860 : vstate.maxbufsize = 0;
1229 2860 : vstate.pendingpages = NULL;
1230 2860 : vstate.npendingpages = 0;
1231 : /* Consider applying _bt_pendingfsm_finalize optimization */
1232 2860 : _bt_pendingfsm_init(rel, &vstate, (callback == NULL));
1233 :
1234 : /*
1235 : * The outer loop iterates over all index pages except the metapage, in
1236 : * physical order (we hope the kernel will cooperate in providing
1237 : * read-ahead for speed). It is critical that we visit all leaf pages,
1238 : * including ones added after we start the scan, else we might fail to
1239 : * delete some deletable tuples. Hence, we must repeatedly check the
1240 : * relation length. We must acquire the relation-extension lock while
1241 : * doing so to avoid a race condition: if someone else is extending the
1242 : * relation, there is a window where bufmgr/smgr have created a new
1243 : * all-zero page but it hasn't yet been write-locked by _bt_getbuf(). If
1244 : * we manage to scan such a page here, we'll improperly assume it can be
1245 : * recycled. Taking the lock synchronizes things enough to prevent a
1246 : * problem: either num_pages won't include the new page, or _bt_getbuf
1247 : * already has write lock on the buffer and it will be fully initialized
1248 : * before we can examine it. Also, we need not worry if a page is added
1249 : * immediately after we look; the page splitting code already has
1250 : * write-lock on the left page before it adds a right page, so we must
1251 : * already have processed any tuples due to be moved into such a page.
1252 : *
1253 : * XXX: Now that new pages are locked with RBM_ZERO_AND_LOCK, I don't
1254 : * think the use of the extension lock is still required.
1255 : *
1256 : * We can skip locking for new or temp relations, however, since no one
1257 : * else could be accessing them.
1258 : */
1259 2860 : needLock = !RELATION_IS_LOCAL(rel);
1260 :
1261 2860 : p.current_blocknum = BTREE_METAPAGE + 1;
1262 :
1263 : /*
1264 : * It is safe to use batchmode as block_range_read_stream_cb takes no
1265 : * locks.
1266 : */
1267 2860 : stream = read_stream_begin_relation(READ_STREAM_MAINTENANCE |
1268 : READ_STREAM_FULL |
1269 : READ_STREAM_USE_BATCHING,
1270 : info->strategy,
1271 : rel,
1272 : MAIN_FORKNUM,
1273 : block_range_read_stream_cb,
1274 : &p,
1275 : 0);
1276 : for (;;)
1277 : {
1278 : /* Get the current relation length */
1279 5446 : if (needLock)
1280 5442 : LockRelationForExtension(rel, ExclusiveLock);
1281 5446 : num_pages = RelationGetNumberOfBlocks(rel);
1282 5446 : if (needLock)
1283 5442 : UnlockRelationForExtension(rel, ExclusiveLock);
1284 :
1285 5446 : if (info->report_progress)
1286 918 : pgstat_progress_update_param(PROGRESS_SCAN_BLOCKS_TOTAL,
1287 : num_pages);
1288 :
1289 : /* Quit if we've scanned the whole relation */
1290 5446 : if (p.current_blocknum >= num_pages)
1291 2860 : break;
1292 :
1293 2586 : p.last_exclusive = num_pages;
1294 :
1295 : /* Iterate over pages, then loop back to recheck relation length */
1296 : while (true)
1297 24810 : {
1298 : BlockNumber current_block;
1299 : Buffer buf;
1300 :
1301 : /* call vacuum_delay_point while not holding any buffer lock */
1302 27396 : vacuum_delay_point(false);
1303 :
1304 27396 : buf = read_stream_next_buffer(stream, NULL);
1305 :
1306 27396 : if (!BufferIsValid(buf))
1307 2586 : break;
1308 :
1309 24810 : current_block = btvacuumpage(&vstate, buf);
1310 :
1311 24810 : if (info->report_progress)
1312 964 : pgstat_progress_update_param(PROGRESS_SCAN_BLOCKS_DONE,
1313 : current_block);
1314 : }
1315 :
1316 : /*
1317 : * We have to reset the read stream to use it again. After returning
1318 : * InvalidBuffer, the read stream API won't invoke our callback again
1319 : * until the stream has been reset.
1320 : */
1321 2586 : read_stream_reset(stream);
1322 : }
1323 :
1324 2860 : read_stream_end(stream);
1325 :
1326 : /* Set statistics num_pages field to final size of index */
1327 2860 : stats->num_pages = num_pages;
1328 :
1329 2860 : MemoryContextDelete(vstate.pagedelcontext);
1330 :
1331 : /*
1332 : * If there were any calls to _bt_pagedel() during scan of the index then
1333 : * see if any of the resulting pages can be placed in the FSM now. When
1334 : * it's not safe we'll have to leave it up to a future VACUUM operation.
1335 : *
1336 : * Finally, if we placed any pages in the FSM (either just now or during
1337 : * the scan), forcibly update the upper-level FSM pages to ensure that
1338 : * searchers can find them.
1339 : */
1340 2860 : _bt_pendingfsm_finalize(rel, &vstate);
1341 2860 : if (stats->pages_free > 0)
1342 48 : IndexFreeSpaceMapVacuum(rel);
1343 2860 : }
1344 :
1345 : /*
1346 : * btvacuumpage --- VACUUM one page
1347 : *
1348 : * This processes a single page for btvacuumscan(). In some cases we must
1349 : * backtrack to re-examine and VACUUM pages that were on buf's page during
1350 : * a previous call here. This is how we handle page splits (that happened
1351 : * after our cycleid was acquired) whose right half page happened to reuse
1352 : * a block that we might have processed at some point before it was
1353 : * recycled (i.e. before the page split).
1354 : *
1355 : * Returns BlockNumber of a scanned page (not backtracked).
1356 : */
1357 : static BlockNumber
1358 24810 : btvacuumpage(BTVacState *vstate, Buffer buf)
1359 : {
1360 24810 : IndexVacuumInfo *info = vstate->info;
1361 24810 : IndexBulkDeleteResult *stats = vstate->stats;
1362 24810 : IndexBulkDeleteCallback callback = vstate->callback;
1363 24810 : void *callback_state = vstate->callback_state;
1364 24810 : Relation rel = info->index;
1365 24810 : Relation heaprel = info->heaprel;
1366 : bool attempt_pagedel;
1367 : BlockNumber blkno,
1368 : backtrack_to;
1369 24810 : BlockNumber scanblkno = BufferGetBlockNumber(buf);
1370 : Page page;
1371 : BTPageOpaque opaque;
1372 :
1373 24810 : blkno = scanblkno;
1374 :
1375 24810 : backtrack:
1376 :
1377 24810 : attempt_pagedel = false;
1378 24810 : backtrack_to = P_NONE;
1379 :
1380 24810 : _bt_lockbuf(rel, buf, BT_READ);
1381 24810 : page = BufferGetPage(buf);
1382 24810 : opaque = NULL;
1383 24810 : if (!PageIsNew(page))
1384 : {
1385 24810 : _bt_checkpage(rel, buf);
1386 24810 : opaque = BTPageGetOpaque(page);
1387 : }
1388 :
1389 : Assert(blkno <= scanblkno);
1390 24810 : if (blkno != scanblkno)
1391 : {
1392 : /*
1393 : * We're backtracking.
1394 : *
1395 : * We followed a right link to a sibling leaf page (a page that
1396 : * happens to be from a block located before scanblkno). The only
1397 : * case we want to do anything with is a live leaf page having the
1398 : * current vacuum cycle ID.
1399 : *
1400 : * The page had better be in a state that's consistent with what we
1401 : * expect. Check for conditions that imply corruption in passing. It
1402 : * can't be half-dead because only an interrupted VACUUM process can
1403 : * leave pages in that state, so we'd definitely have dealt with it
1404 : * back when the page was the scanblkno page (half-dead pages are
1405 : * always marked fully deleted by _bt_pagedel(), barring corruption).
1406 : */
1407 0 : if (!opaque || !P_ISLEAF(opaque) || P_ISHALFDEAD(opaque))
1408 : {
1409 : Assert(false);
1410 0 : ereport(LOG,
1411 : (errcode(ERRCODE_INDEX_CORRUPTED),
1412 : errmsg_internal("right sibling %u of scanblkno %u unexpectedly in an inconsistent state in index \"%s\"",
1413 : blkno, scanblkno, RelationGetRelationName(rel))));
1414 0 : _bt_relbuf(rel, buf);
1415 0 : return scanblkno;
1416 : }
1417 :
1418 : /*
1419 : * We may have already processed the page in an earlier call, when the
1420 : * page was scanblkno. This happens when the leaf page split occurred
1421 : * after the scan began, but before the right sibling page became the
1422 : * scanblkno.
1423 : *
1424 : * Page may also have been deleted by current btvacuumpage() call,
1425 : * since _bt_pagedel() sometimes deletes the right sibling page of
1426 : * scanblkno in passing (it does so after we decided where to
1427 : * backtrack to). We don't need to process this page as a deleted
1428 : * page a second time now (in fact, it would be wrong to count it as a
1429 : * deleted page in the bulk delete statistics a second time).
1430 : */
1431 0 : if (opaque->btpo_cycleid != vstate->cycleid || P_ISDELETED(opaque))
1432 : {
1433 : /* Done with current scanblkno (and all lower split pages) */
1434 0 : _bt_relbuf(rel, buf);
1435 0 : return scanblkno;
1436 : }
1437 : }
1438 :
1439 24810 : if (!opaque || BTPageIsRecyclable(page, heaprel))
1440 : {
1441 : /* Okay to recycle this page (which could be leaf or internal) */
1442 278 : RecordFreeIndexPage(rel, blkno);
1443 278 : stats->pages_deleted++;
1444 278 : stats->pages_free++;
1445 : }
1446 24532 : else if (P_ISDELETED(opaque))
1447 : {
1448 : /*
1449 : * Already deleted page (which could be leaf or internal). Can't
1450 : * recycle yet.
1451 : */
1452 38 : stats->pages_deleted++;
1453 : }
1454 24494 : else if (P_ISHALFDEAD(opaque))
1455 : {
1456 : /* Half-dead leaf page (from interrupted VACUUM) -- finish deleting */
1457 0 : attempt_pagedel = true;
1458 :
1459 : /*
1460 : * _bt_pagedel() will increment both pages_newly_deleted and
1461 : * pages_deleted stats in all cases (barring corruption)
1462 : */
1463 : }
1464 24494 : else if (P_ISLEAF(opaque))
1465 : {
1466 : OffsetNumber deletable[MaxIndexTuplesPerPage];
1467 : int ndeletable;
1468 : BTVacuumPosting updatable[MaxIndexTuplesPerPage];
1469 : int nupdatable;
1470 : OffsetNumber offnum,
1471 : minoff,
1472 : maxoff;
1473 : int nhtidsdead,
1474 : nhtidslive;
1475 :
1476 : /*
1477 : * Trade in the initial read lock for a full cleanup lock on this
1478 : * page. We must get such a lock on every leaf page over the course
1479 : * of the vacuum scan, whether or not it actually contains any
1480 : * deletable tuples --- see nbtree/README.
1481 : */
1482 22986 : _bt_upgradelockbufcleanup(rel, buf);
1483 :
1484 : /*
1485 : * Check whether we need to backtrack to earlier pages. What we are
1486 : * concerned about is a page split that happened since we started the
1487 : * vacuum scan. If the split moved tuples on the right half of the
1488 : * split (i.e. the tuples that sort high) to a block that we already
1489 : * passed over, then we might have missed the tuples. We need to
1490 : * backtrack now. (Must do this before possibly clearing btpo_cycleid
1491 : * or deleting scanblkno page below!)
1492 : */
1493 22986 : if (vstate->cycleid != 0 &&
1494 22870 : opaque->btpo_cycleid == vstate->cycleid &&
1495 0 : !(opaque->btpo_flags & BTP_SPLIT_END) &&
1496 0 : !P_RIGHTMOST(opaque) &&
1497 0 : opaque->btpo_next < scanblkno)
1498 0 : backtrack_to = opaque->btpo_next;
1499 :
1500 22986 : ndeletable = 0;
1501 22986 : nupdatable = 0;
1502 22986 : minoff = P_FIRSTDATAKEY(opaque);
1503 22986 : maxoff = PageGetMaxOffsetNumber(page);
1504 22986 : nhtidsdead = 0;
1505 22986 : nhtidslive = 0;
1506 22986 : if (callback)
1507 : {
1508 : /* btbulkdelete callback tells us what to delete (or update) */
1509 22870 : for (offnum = minoff;
1510 4473482 : offnum <= maxoff;
1511 4450612 : offnum = OffsetNumberNext(offnum))
1512 : {
1513 : IndexTuple itup;
1514 :
1515 4450612 : itup = (IndexTuple) PageGetItem(page,
1516 4450612 : PageGetItemId(page, offnum));
1517 :
1518 : Assert(!BTreeTupleIsPivot(itup));
1519 4450612 : if (!BTreeTupleIsPosting(itup))
1520 : {
1521 : /* Regular tuple, standard table TID representation */
1522 4310334 : if (callback(&itup->t_tid, callback_state))
1523 : {
1524 1623616 : deletable[ndeletable++] = offnum;
1525 1623616 : nhtidsdead++;
1526 : }
1527 : else
1528 2686718 : nhtidslive++;
1529 : }
1530 : else
1531 : {
1532 : BTVacuumPosting vacposting;
1533 : int nremaining;
1534 :
1535 : /* Posting list tuple */
1536 140278 : vacposting = btreevacuumposting(vstate, itup, offnum,
1537 : &nremaining);
1538 140278 : if (vacposting == NULL)
1539 : {
1540 : /*
1541 : * All table TIDs from the posting tuple remain, so no
1542 : * delete or update required
1543 : */
1544 : Assert(nremaining == BTreeTupleGetNPosting(itup));
1545 : }
1546 87042 : else if (nremaining > 0)
1547 : {
1548 :
1549 : /*
1550 : * Store metadata about posting list tuple in
1551 : * updatable array for entire page. Existing tuple
1552 : * will be updated during the later call to
1553 : * _bt_delitems_vacuum().
1554 : */
1555 : Assert(nremaining < BTreeTupleGetNPosting(itup));
1556 39896 : updatable[nupdatable++] = vacposting;
1557 39896 : nhtidsdead += BTreeTupleGetNPosting(itup) - nremaining;
1558 : }
1559 : else
1560 : {
1561 : /*
1562 : * All table TIDs from the posting list must be
1563 : * deleted. We'll delete the index tuple completely
1564 : * (no update required).
1565 : */
1566 : Assert(nremaining == 0);
1567 47146 : deletable[ndeletable++] = offnum;
1568 47146 : nhtidsdead += BTreeTupleGetNPosting(itup);
1569 47146 : pfree(vacposting);
1570 : }
1571 :
1572 140278 : nhtidslive += nremaining;
1573 : }
1574 : }
1575 : }
1576 :
1577 : /*
1578 : * Apply any needed deletes or updates. We issue just one
1579 : * _bt_delitems_vacuum() call per page, so as to minimize WAL traffic.
1580 : */
1581 22986 : if (ndeletable > 0 || nupdatable > 0)
1582 : {
1583 : Assert(nhtidsdead >= ndeletable + nupdatable);
1584 14638 : _bt_delitems_vacuum(rel, buf, deletable, ndeletable, updatable,
1585 : nupdatable);
1586 :
1587 14638 : stats->tuples_removed += nhtidsdead;
1588 : /* must recompute maxoff */
1589 14638 : maxoff = PageGetMaxOffsetNumber(page);
1590 :
1591 : /* can't leak memory here */
1592 54534 : for (int i = 0; i < nupdatable; i++)
1593 39896 : pfree(updatable[i]);
1594 : }
1595 : else
1596 : {
1597 : /*
1598 : * If the leaf page has been split during this vacuum cycle, it
1599 : * seems worth expending a write to clear btpo_cycleid even if we
1600 : * don't have any deletions to do. (If we do, _bt_delitems_vacuum
1601 : * takes care of this.) This ensures we won't process the page
1602 : * again.
1603 : *
1604 : * We treat this like a hint-bit update because there's no need to
1605 : * WAL-log it.
1606 : */
1607 : Assert(nhtidsdead == 0);
1608 8348 : if (vstate->cycleid != 0 &&
1609 8232 : opaque->btpo_cycleid == vstate->cycleid)
1610 : {
1611 0 : opaque->btpo_cycleid = 0;
1612 0 : MarkBufferDirtyHint(buf, true);
1613 : }
1614 : }
1615 :
1616 : /*
1617 : * If the leaf page is now empty, try to delete it; else count the
1618 : * live tuples (live table TIDs in posting lists are counted as
1619 : * separate live tuples). We don't delete when backtracking, though,
1620 : * since that would require teaching _bt_pagedel() about backtracking
1621 : * (doesn't seem worth adding more complexity to deal with that).
1622 : *
1623 : * We don't count the number of live TIDs during cleanup-only calls to
1624 : * btvacuumscan (i.e. when callback is not set). We count the number
1625 : * of index tuples directly instead. This avoids the expense of
1626 : * directly examining all of the tuples on each page. VACUUM will
1627 : * treat num_index_tuples as an estimate in cleanup-only case, so it
1628 : * doesn't matter that this underestimates num_index_tuples
1629 : * significantly in some cases.
1630 : */
1631 22986 : if (minoff > maxoff)
1632 5646 : attempt_pagedel = (blkno == scanblkno);
1633 17340 : else if (callback)
1634 17232 : stats->num_index_tuples += nhtidslive;
1635 : else
1636 108 : stats->num_index_tuples += maxoff - minoff + 1;
1637 :
1638 : Assert(!attempt_pagedel || nhtidslive == 0);
1639 : }
1640 :
1641 24810 : if (attempt_pagedel)
1642 : {
1643 : MemoryContext oldcontext;
1644 :
1645 : /* Run pagedel in a temp context to avoid memory leakage */
1646 5646 : MemoryContextReset(vstate->pagedelcontext);
1647 5646 : oldcontext = MemoryContextSwitchTo(vstate->pagedelcontext);
1648 :
1649 : /*
1650 : * _bt_pagedel maintains the bulk delete stats on our behalf;
1651 : * pages_newly_deleted and pages_deleted are likely to be incremented
1652 : * during call
1653 : */
1654 : Assert(blkno == scanblkno);
1655 5646 : _bt_pagedel(rel, buf, vstate);
1656 :
1657 5646 : MemoryContextSwitchTo(oldcontext);
1658 : /* pagedel released buffer, so we shouldn't */
1659 : }
1660 : else
1661 19164 : _bt_relbuf(rel, buf);
1662 :
1663 24810 : if (backtrack_to != P_NONE)
1664 : {
1665 0 : blkno = backtrack_to;
1666 :
1667 : /* check for vacuum delay while not holding any buffer lock */
1668 0 : vacuum_delay_point(false);
1669 :
1670 : /*
1671 : * We can't use _bt_getbuf() here because it always applies
1672 : * _bt_checkpage(), which will barf on an all-zero page. We want to
1673 : * recycle all-zero pages, not fail. Also, we want to use a
1674 : * nondefault buffer access strategy.
1675 : */
1676 0 : buf = ReadBufferExtended(rel, MAIN_FORKNUM, blkno, RBM_NORMAL,
1677 : info->strategy);
1678 0 : goto backtrack;
1679 : }
1680 :
1681 24810 : return scanblkno;
1682 : }
1683 :
1684 : /*
1685 : * btreevacuumposting --- determine TIDs still needed in posting list
1686 : *
1687 : * Returns metadata describing how to build replacement tuple without the TIDs
1688 : * that VACUUM needs to delete. Returned value is NULL in the common case
1689 : * where no changes are needed to caller's posting list tuple (we avoid
1690 : * allocating memory here as an optimization).
1691 : *
1692 : * The number of TIDs that should remain in the posting list tuple is set for
1693 : * caller in *nremaining.
1694 : */
1695 : static BTVacuumPosting
1696 140278 : btreevacuumposting(BTVacState *vstate, IndexTuple posting,
1697 : OffsetNumber updatedoffset, int *nremaining)
1698 : {
1699 140278 : int live = 0;
1700 140278 : int nitem = BTreeTupleGetNPosting(posting);
1701 140278 : ItemPointer items = BTreeTupleGetPosting(posting);
1702 140278 : BTVacuumPosting vacposting = NULL;
1703 :
1704 787912 : for (int i = 0; i < nitem; i++)
1705 : {
1706 647634 : if (!vstate->callback(items + i, vstate->callback_state))
1707 : {
1708 : /* Live table TID */
1709 351916 : live++;
1710 : }
1711 295718 : else if (vacposting == NULL)
1712 : {
1713 : /*
1714 : * First dead table TID encountered.
1715 : *
1716 : * It's now clear that we need to delete one or more dead table
1717 : * TIDs, so start maintaining metadata describing how to update
1718 : * existing posting list tuple.
1719 : */
1720 87042 : vacposting = palloc(offsetof(BTVacuumPostingData, deletetids) +
1721 : nitem * sizeof(uint16));
1722 :
1723 87042 : vacposting->itup = posting;
1724 87042 : vacposting->updatedoffset = updatedoffset;
1725 87042 : vacposting->ndeletedtids = 0;
1726 87042 : vacposting->deletetids[vacposting->ndeletedtids++] = i;
1727 : }
1728 : else
1729 : {
1730 : /* Second or subsequent dead table TID */
1731 208676 : vacposting->deletetids[vacposting->ndeletedtids++] = i;
1732 : }
1733 : }
1734 :
1735 140278 : *nremaining = live;
1736 140278 : return vacposting;
1737 : }
1738 :
1739 : /*
1740 : * btcanreturn() -- Check whether btree indexes support index-only scans.
1741 : *
1742 : * btrees always do, so this is trivial.
1743 : */
1744 : bool
1745 1121858 : btcanreturn(Relation index, int attno)
1746 : {
1747 1121858 : return true;
1748 : }
1749 :
1750 : /*
1751 : * btgettreeheight() -- Compute tree height for use by btcostestimate().
1752 : */
1753 : int
1754 716384 : btgettreeheight(Relation rel)
1755 : {
1756 716384 : return _bt_getrootheight(rel);
1757 : }
1758 :
1759 : CompareType
1760 0 : bttranslatestrategy(StrategyNumber strategy, Oid opfamily)
1761 : {
1762 0 : switch (strategy)
1763 : {
1764 0 : case BTLessStrategyNumber:
1765 0 : return COMPARE_LT;
1766 0 : case BTLessEqualStrategyNumber:
1767 0 : return COMPARE_LE;
1768 0 : case BTEqualStrategyNumber:
1769 0 : return COMPARE_EQ;
1770 0 : case BTGreaterEqualStrategyNumber:
1771 0 : return COMPARE_GE;
1772 0 : case BTGreaterStrategyNumber:
1773 0 : return COMPARE_GT;
1774 0 : default:
1775 0 : return COMPARE_INVALID;
1776 : }
1777 : }
1778 :
1779 : StrategyNumber
1780 0 : bttranslatecmptype(CompareType cmptype, Oid opfamily)
1781 : {
1782 0 : switch (cmptype)
1783 : {
1784 0 : case COMPARE_LT:
1785 0 : return BTLessStrategyNumber;
1786 0 : case COMPARE_LE:
1787 0 : return BTLessEqualStrategyNumber;
1788 0 : case COMPARE_EQ:
1789 0 : return BTEqualStrategyNumber;
1790 0 : case COMPARE_GE:
1791 0 : return BTGreaterEqualStrategyNumber;
1792 0 : case COMPARE_GT:
1793 0 : return BTGreaterStrategyNumber;
1794 0 : default:
1795 0 : return InvalidStrategy;
1796 : }
1797 : }
|
