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vacuum.c
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1 /*-------------------------------------------------------------------------
2  *
3  * vacuum.c
4  * The postgres vacuum cleaner.
5  *
6  * This file now includes only control and dispatch code for VACUUM and
7  * ANALYZE commands. Regular VACUUM is implemented in vacuumlazy.c,
8  * ANALYZE in analyze.c, and VACUUM FULL is a variant of CLUSTER, handled
9  * in cluster.c.
10  *
11  *
12  * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
13  * Portions Copyright (c) 1994, Regents of the University of California
14  *
15  *
16  * IDENTIFICATION
17  * src/backend/commands/vacuum.c
18  *
19  *-------------------------------------------------------------------------
20  */
21 #include "postgres.h"
22 
23 #include <math.h>
24 
25 #include "access/clog.h"
26 #include "access/commit_ts.h"
27 #include "access/genam.h"
28 #include "access/heapam.h"
29 #include "access/htup_details.h"
30 #include "access/multixact.h"
31 #include "access/tableam.h"
32 #include "access/transam.h"
33 #include "access/xact.h"
34 #include "catalog/namespace.h"
35 #include "catalog/pg_database.h"
36 #include "catalog/pg_inherits.h"
37 #include "catalog/pg_namespace.h"
38 #include "commands/cluster.h"
39 #include "commands/defrem.h"
40 #include "commands/vacuum.h"
41 #include "miscadmin.h"
42 #include "nodes/makefuncs.h"
43 #include "pgstat.h"
44 #include "postmaster/autovacuum.h"
46 #include "storage/bufmgr.h"
47 #include "storage/lmgr.h"
48 #include "storage/proc.h"
49 #include "storage/procarray.h"
50 #include "utils/acl.h"
51 #include "utils/fmgroids.h"
52 #include "utils/guc.h"
53 #include "utils/memutils.h"
54 #include "utils/snapmgr.h"
55 #include "utils/syscache.h"
56 
57 
58 /*
59  * GUC parameters
60  */
65 
66 
67 /* A few variables that don't seem worth passing around as parameters */
68 static MemoryContext vac_context = NULL;
70 
71 
72 /*
73  * Variables for cost-based parallel vacuum. See comments atop
74  * compute_parallel_delay to understand how it works.
75  */
79 
80 /* non-export function prototypes */
81 static List *expand_vacuum_rel(VacuumRelation *vrel, int options);
82 static List *get_all_vacuum_rels(int options);
83 static void vac_truncate_clog(TransactionId frozenXID,
84  MultiXactId minMulti,
85  TransactionId lastSaneFrozenXid,
86  MultiXactId lastSaneMinMulti);
87 static bool vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params);
88 static double compute_parallel_delay(void);
90 
91 /*
92  * Primary entry point for manual VACUUM and ANALYZE commands
93  *
94  * This is mainly a preparation wrapper for the real operations that will
95  * happen in vacuum().
96  */
97 void
98 ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
99 {
100  VacuumParams params;
101  bool verbose = false;
102  bool skip_locked = false;
103  bool analyze = false;
104  bool freeze = false;
105  bool full = false;
106  bool disable_page_skipping = false;
107  ListCell *lc;
108 
109  /* Set default value */
112 
113  /* By default parallel vacuum is enabled */
114  params.nworkers = 0;
115 
116  /* Parse options list */
117  foreach(lc, vacstmt->options)
118  {
119  DefElem *opt = (DefElem *) lfirst(lc);
120 
121  /* Parse common options for VACUUM and ANALYZE */
122  if (strcmp(opt->defname, "verbose") == 0)
123  verbose = defGetBoolean(opt);
124  else if (strcmp(opt->defname, "skip_locked") == 0)
125  skip_locked = defGetBoolean(opt);
126  else if (!vacstmt->is_vacuumcmd)
127  ereport(ERROR,
128  (errcode(ERRCODE_SYNTAX_ERROR),
129  errmsg("unrecognized ANALYZE option \"%s\"", opt->defname),
130  parser_errposition(pstate, opt->location)));
131 
132  /* Parse options available on VACUUM */
133  else if (strcmp(opt->defname, "analyze") == 0)
134  analyze = defGetBoolean(opt);
135  else if (strcmp(opt->defname, "freeze") == 0)
136  freeze = defGetBoolean(opt);
137  else if (strcmp(opt->defname, "full") == 0)
138  full = defGetBoolean(opt);
139  else if (strcmp(opt->defname, "disable_page_skipping") == 0)
140  disable_page_skipping = defGetBoolean(opt);
141  else if (strcmp(opt->defname, "index_cleanup") == 0)
143  else if (strcmp(opt->defname, "truncate") == 0)
144  params.truncate = get_vacopt_ternary_value(opt);
145  else if (strcmp(opt->defname, "parallel") == 0)
146  {
147  if (opt->arg == NULL)
148  {
149  ereport(ERROR,
150  (errcode(ERRCODE_SYNTAX_ERROR),
151  errmsg("parallel option requires a value between 0 and %d",
153  parser_errposition(pstate, opt->location)));
154  }
155  else
156  {
157  int nworkers;
158 
159  nworkers = defGetInt32(opt);
160  if (nworkers < 0 || nworkers > MAX_PARALLEL_WORKER_LIMIT)
161  ereport(ERROR,
162  (errcode(ERRCODE_SYNTAX_ERROR),
163  errmsg("parallel vacuum degree must be between 0 and %d",
164  MAX_PARALLEL_WORKER_LIMIT),
165  parser_errposition(pstate, opt->location)));
166 
167  /*
168  * Disable parallel vacuum, if user has specified parallel
169  * degree as zero.
170  */
171  if (nworkers == 0)
172  params.nworkers = -1;
173  else
174  params.nworkers = nworkers;
175  }
176  }
177  else
178  ereport(ERROR,
179  (errcode(ERRCODE_SYNTAX_ERROR),
180  errmsg("unrecognized VACUUM option \"%s\"", opt->defname),
181  parser_errposition(pstate, opt->location)));
182  }
183 
184  /* Set vacuum options */
185  params.options =
186  (vacstmt->is_vacuumcmd ? VACOPT_VACUUM : VACOPT_ANALYZE) |
187  (verbose ? VACOPT_VERBOSE : 0) |
188  (skip_locked ? VACOPT_SKIP_LOCKED : 0) |
189  (analyze ? VACOPT_ANALYZE : 0) |
190  (freeze ? VACOPT_FREEZE : 0) |
191  (full ? VACOPT_FULL : 0) |
192  (disable_page_skipping ? VACOPT_DISABLE_PAGE_SKIPPING : 0);
193 
194  /* sanity checks on options */
195  Assert(params.options & (VACOPT_VACUUM | VACOPT_ANALYZE));
196  Assert((params.options & VACOPT_VACUUM) ||
197  !(params.options & (VACOPT_FULL | VACOPT_FREEZE)));
198  Assert(!(params.options & VACOPT_SKIPTOAST));
199 
200  if ((params.options & VACOPT_FULL) && params.nworkers > 0)
201  ereport(ERROR,
202  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
203  errmsg("VACUUM FULL cannot be performed in parallel")));
204 
205  /*
206  * Make sure VACOPT_ANALYZE is specified if any column lists are present.
207  */
208  if (!(params.options & VACOPT_ANALYZE))
209  {
210  ListCell *lc;
211 
212  foreach(lc, vacstmt->rels)
213  {
215 
216  if (vrel->va_cols != NIL)
217  ereport(ERROR,
218  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
219  errmsg("ANALYZE option must be specified when a column list is provided")));
220  }
221  }
222 
223  /*
224  * All freeze ages are zero if the FREEZE option is given; otherwise pass
225  * them as -1 which means to use the default values.
226  */
227  if (params.options & VACOPT_FREEZE)
228  {
229  params.freeze_min_age = 0;
230  params.freeze_table_age = 0;
231  params.multixact_freeze_min_age = 0;
232  params.multixact_freeze_table_age = 0;
233  }
234  else
235  {
236  params.freeze_min_age = -1;
237  params.freeze_table_age = -1;
238  params.multixact_freeze_min_age = -1;
239  params.multixact_freeze_table_age = -1;
240  }
241 
242  /* user-invoked vacuum is never "for wraparound" */
243  params.is_wraparound = false;
244 
245  /* user-invoked vacuum never uses this parameter */
246  params.log_min_duration = -1;
247 
248  /* Now go through the common routine */
249  vacuum(vacstmt->rels, &params, NULL, isTopLevel);
250 }
251 
252 /*
253  * Internal entry point for VACUUM and ANALYZE commands.
254  *
255  * relations, if not NIL, is a list of VacuumRelation to process; otherwise,
256  * we process all relevant tables in the database. For each VacuumRelation,
257  * if a valid OID is supplied, the table with that OID is what to process;
258  * otherwise, the VacuumRelation's RangeVar indicates what to process.
259  *
260  * params contains a set of parameters that can be used to customize the
261  * behavior.
262  *
263  * bstrategy is normally given as NULL, but in autovacuum it can be passed
264  * in to use the same buffer strategy object across multiple vacuum() calls.
265  *
266  * isTopLevel should be passed down from ProcessUtility.
267  *
268  * It is the caller's responsibility that all parameters are allocated in a
269  * memory context that will not disappear at transaction commit.
270  */
271 void
272 vacuum(List *relations, VacuumParams *params,
273  BufferAccessStrategy bstrategy, bool isTopLevel)
274 {
275  static bool in_vacuum = false;
276 
277  const char *stmttype;
278  volatile bool in_outer_xact,
279  use_own_xacts;
280 
281  Assert(params != NULL);
282 
283  stmttype = (params->options & VACOPT_VACUUM) ? "VACUUM" : "ANALYZE";
284 
285  /*
286  * We cannot run VACUUM inside a user transaction block; if we were inside
287  * a transaction, then our commit- and start-transaction-command calls
288  * would not have the intended effect! There are numerous other subtle
289  * dependencies on this, too.
290  *
291  * ANALYZE (without VACUUM) can run either way.
292  */
293  if (params->options & VACOPT_VACUUM)
294  {
295  PreventInTransactionBlock(isTopLevel, stmttype);
296  in_outer_xact = false;
297  }
298  else
299  in_outer_xact = IsInTransactionBlock(isTopLevel);
300 
301  /*
302  * Due to static variables vac_context, anl_context and vac_strategy,
303  * vacuum() is not reentrant. This matters when VACUUM FULL or ANALYZE
304  * calls a hostile index expression that itself calls ANALYZE.
305  */
306  if (in_vacuum)
307  ereport(ERROR,
308  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
309  errmsg("%s cannot be executed from VACUUM or ANALYZE",
310  stmttype)));
311 
312  /*
313  * Sanity check DISABLE_PAGE_SKIPPING option.
314  */
315  if ((params->options & VACOPT_FULL) != 0 &&
316  (params->options & VACOPT_DISABLE_PAGE_SKIPPING) != 0)
317  ereport(ERROR,
318  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
319  errmsg("VACUUM option DISABLE_PAGE_SKIPPING cannot be used with FULL")));
320 
321  /*
322  * Send info about dead objects to the statistics collector, unless we are
323  * in autovacuum --- autovacuum.c does this for itself.
324  */
325  if ((params->options & VACOPT_VACUUM) && !IsAutoVacuumWorkerProcess())
327 
328  /*
329  * Create special memory context for cross-transaction storage.
330  *
331  * Since it is a child of PortalContext, it will go away eventually even
332  * if we suffer an error; there's no need for special abort cleanup logic.
333  */
334  vac_context = AllocSetContextCreate(PortalContext,
335  "Vacuum",
337 
338  /*
339  * If caller didn't give us a buffer strategy object, make one in the
340  * cross-transaction memory context.
341  */
342  if (bstrategy == NULL)
343  {
344  MemoryContext old_context = MemoryContextSwitchTo(vac_context);
345 
346  bstrategy = GetAccessStrategy(BAS_VACUUM);
347  MemoryContextSwitchTo(old_context);
348  }
349  vac_strategy = bstrategy;
350 
351  /*
352  * Build list of relation(s) to process, putting any new data in
353  * vac_context for safekeeping.
354  */
355  if (relations != NIL)
356  {
357  List *newrels = NIL;
358  ListCell *lc;
359 
360  foreach(lc, relations)
361  {
363  List *sublist;
364  MemoryContext old_context;
365 
366  sublist = expand_vacuum_rel(vrel, params->options);
367  old_context = MemoryContextSwitchTo(vac_context);
368  newrels = list_concat(newrels, sublist);
369  MemoryContextSwitchTo(old_context);
370  }
371  relations = newrels;
372  }
373  else
374  relations = get_all_vacuum_rels(params->options);
375 
376  /*
377  * Decide whether we need to start/commit our own transactions.
378  *
379  * For VACUUM (with or without ANALYZE): always do so, so that we can
380  * release locks as soon as possible. (We could possibly use the outer
381  * transaction for a one-table VACUUM, but handling TOAST tables would be
382  * problematic.)
383  *
384  * For ANALYZE (no VACUUM): if inside a transaction block, we cannot
385  * start/commit our own transactions. Also, there's no need to do so if
386  * only processing one relation. For multiple relations when not within a
387  * transaction block, and also in an autovacuum worker, use own
388  * transactions so we can release locks sooner.
389  */
390  if (params->options & VACOPT_VACUUM)
391  use_own_xacts = true;
392  else
393  {
394  Assert(params->options & VACOPT_ANALYZE);
396  use_own_xacts = true;
397  else if (in_outer_xact)
398  use_own_xacts = false;
399  else if (list_length(relations) > 1)
400  use_own_xacts = true;
401  else
402  use_own_xacts = false;
403  }
404 
405  /*
406  * vacuum_rel expects to be entered with no transaction active; it will
407  * start and commit its own transaction. But we are called by an SQL
408  * command, and so we are executing inside a transaction already. We
409  * commit the transaction started in PostgresMain() here, and start
410  * another one before exiting to match the commit waiting for us back in
411  * PostgresMain().
412  */
413  if (use_own_xacts)
414  {
415  Assert(!in_outer_xact);
416 
417  /* ActiveSnapshot is not set by autovacuum */
418  if (ActiveSnapshotSet())
420 
421  /* matches the StartTransaction in PostgresMain() */
423  }
424 
425  /* Turn vacuum cost accounting on or off, and set/clear in_vacuum */
426  PG_TRY();
427  {
428  ListCell *cur;
429 
430  in_vacuum = true;
432  VacuumCostBalance = 0;
433  VacuumPageHit = 0;
434  VacuumPageMiss = 0;
435  VacuumPageDirty = 0;
437  VacuumSharedCostBalance = NULL;
438  VacuumActiveNWorkers = NULL;
439 
440  /*
441  * Loop to process each selected relation.
442  */
443  foreach(cur, relations)
444  {
446 
447  if (params->options & VACOPT_VACUUM)
448  {
449  if (!vacuum_rel(vrel->oid, vrel->relation, params))
450  continue;
451  }
452 
453  if (params->options & VACOPT_ANALYZE)
454  {
455  /*
456  * If using separate xacts, start one for analyze. Otherwise,
457  * we can use the outer transaction.
458  */
459  if (use_own_xacts)
460  {
462  /* functions in indexes may want a snapshot set */
464  }
465 
466  analyze_rel(vrel->oid, vrel->relation, params,
467  vrel->va_cols, in_outer_xact, vac_strategy);
468 
469  if (use_own_xacts)
470  {
473  }
474  else
475  {
476  /*
477  * If we're not using separate xacts, better separate the
478  * ANALYZE actions with CCIs. This avoids trouble if user
479  * says "ANALYZE t, t".
480  */
482  }
483  }
484  }
485  }
486  PG_FINALLY();
487  {
488  in_vacuum = false;
489  VacuumCostActive = false;
490  }
491  PG_END_TRY();
492 
493  /*
494  * Finish up processing.
495  */
496  if (use_own_xacts)
497  {
498  /* here, we are not in a transaction */
499 
500  /*
501  * This matches the CommitTransaction waiting for us in
502  * PostgresMain().
503  */
505  }
506 
507  if ((params->options & VACOPT_VACUUM) && !IsAutoVacuumWorkerProcess())
508  {
509  /*
510  * Update pg_database.datfrozenxid, and truncate pg_xact if possible.
511  * (autovacuum.c does this for itself.)
512  */
514  }
515 
516  /*
517  * Clean up working storage --- note we must do this after
518  * StartTransactionCommand, else we might be trying to delete the active
519  * context!
520  */
521  MemoryContextDelete(vac_context);
522  vac_context = NULL;
523 }
524 
525 /*
526  * Check if a given relation can be safely vacuumed or analyzed. If the
527  * user is not the relation owner, issue a WARNING log message and return
528  * false to let the caller decide what to do with this relation. This
529  * routine is used to decide if a relation can be processed for VACUUM or
530  * ANALYZE.
531  */
532 bool
534 {
535  char *relname;
536 
537  Assert((options & (VACOPT_VACUUM | VACOPT_ANALYZE)) != 0);
538 
539  /*
540  * Check permissions.
541  *
542  * We allow the user to vacuum or analyze a table if he is superuser, the
543  * table owner, or the database owner (but in the latter case, only if
544  * it's not a shared relation). pg_class_ownercheck includes the
545  * superuser case.
546  *
547  * Note we choose to treat permissions failure as a WARNING and keep
548  * trying to vacuum or analyze the rest of the DB --- is this appropriate?
549  */
550  if (pg_class_ownercheck(relid, GetUserId()) ||
551  (pg_database_ownercheck(MyDatabaseId, GetUserId()) && !reltuple->relisshared))
552  return true;
553 
554  relname = NameStr(reltuple->relname);
555 
556  if ((options & VACOPT_VACUUM) != 0)
557  {
558  if (reltuple->relisshared)
560  (errmsg("skipping \"%s\" --- only superuser can vacuum it",
561  relname)));
562  else if (reltuple->relnamespace == PG_CATALOG_NAMESPACE)
564  (errmsg("skipping \"%s\" --- only superuser or database owner can vacuum it",
565  relname)));
566  else
568  (errmsg("skipping \"%s\" --- only table or database owner can vacuum it",
569  relname)));
570 
571  /*
572  * For VACUUM ANALYZE, both logs could show up, but just generate
573  * information for VACUUM as that would be the first one to be
574  * processed.
575  */
576  return false;
577  }
578 
579  if ((options & VACOPT_ANALYZE) != 0)
580  {
581  if (reltuple->relisshared)
583  (errmsg("skipping \"%s\" --- only superuser can analyze it",
584  relname)));
585  else if (reltuple->relnamespace == PG_CATALOG_NAMESPACE)
587  (errmsg("skipping \"%s\" --- only superuser or database owner can analyze it",
588  relname)));
589  else
591  (errmsg("skipping \"%s\" --- only table or database owner can analyze it",
592  relname)));
593  }
594 
595  return false;
596 }
597 
598 
599 /*
600  * vacuum_open_relation
601  *
602  * This routine is used for attempting to open and lock a relation which
603  * is going to be vacuumed or analyzed. If the relation cannot be opened
604  * or locked, a log is emitted if possible.
605  */
606 Relation
607 vacuum_open_relation(Oid relid, RangeVar *relation, int options,
608  bool verbose, LOCKMODE lmode)
609 {
610  Relation onerel;
611  bool rel_lock = true;
612  int elevel;
613 
614  Assert((options & (VACOPT_VACUUM | VACOPT_ANALYZE)) != 0);
615 
616  /*
617  * Open the relation and get the appropriate lock on it.
618  *
619  * There's a race condition here: the relation may have gone away since
620  * the last time we saw it. If so, we don't need to vacuum or analyze it.
621  *
622  * If we've been asked not to wait for the relation lock, acquire it first
623  * in non-blocking mode, before calling try_relation_open().
624  */
625  if (!(options & VACOPT_SKIP_LOCKED))
626  onerel = try_relation_open(relid, lmode);
627  else if (ConditionalLockRelationOid(relid, lmode))
628  onerel = try_relation_open(relid, NoLock);
629  else
630  {
631  onerel = NULL;
632  rel_lock = false;
633  }
634 
635  /* if relation is opened, leave */
636  if (onerel)
637  return onerel;
638 
639  /*
640  * Relation could not be opened, hence generate if possible a log
641  * informing on the situation.
642  *
643  * If the RangeVar is not defined, we do not have enough information to
644  * provide a meaningful log statement. Chances are that the caller has
645  * intentionally not provided this information so that this logging is
646  * skipped, anyway.
647  */
648  if (relation == NULL)
649  return NULL;
650 
651  /*
652  * Determine the log level.
653  *
654  * For manual VACUUM or ANALYZE, we emit a WARNING to match the log
655  * statements in the permission checks; otherwise, only log if the caller
656  * so requested.
657  */
659  elevel = WARNING;
660  else if (verbose)
661  elevel = LOG;
662  else
663  return NULL;
664 
665  if ((options & VACOPT_VACUUM) != 0)
666  {
667  if (!rel_lock)
668  ereport(elevel,
669  (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
670  errmsg("skipping vacuum of \"%s\" --- lock not available",
671  relation->relname)));
672  else
673  ereport(elevel,
675  errmsg("skipping vacuum of \"%s\" --- relation no longer exists",
676  relation->relname)));
677 
678  /*
679  * For VACUUM ANALYZE, both logs could show up, but just generate
680  * information for VACUUM as that would be the first one to be
681  * processed.
682  */
683  return NULL;
684  }
685 
686  if ((options & VACOPT_ANALYZE) != 0)
687  {
688  if (!rel_lock)
689  ereport(elevel,
690  (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
691  errmsg("skipping analyze of \"%s\" --- lock not available",
692  relation->relname)));
693  else
694  ereport(elevel,
696  errmsg("skipping analyze of \"%s\" --- relation no longer exists",
697  relation->relname)));
698  }
699 
700  return NULL;
701 }
702 
703 
704 /*
705  * Given a VacuumRelation, fill in the table OID if it wasn't specified,
706  * and optionally add VacuumRelations for partitions of the table.
707  *
708  * If a VacuumRelation does not have an OID supplied and is a partitioned
709  * table, an extra entry will be added to the output for each partition.
710  * Presently, only autovacuum supplies OIDs when calling vacuum(), and
711  * it does not want us to expand partitioned tables.
712  *
713  * We take care not to modify the input data structure, but instead build
714  * new VacuumRelation(s) to return. (But note that they will reference
715  * unmodified parts of the input, eg column lists.) New data structures
716  * are made in vac_context.
717  */
718 static List *
720 {
721  List *vacrels = NIL;
722  MemoryContext oldcontext;
723 
724  /* If caller supplied OID, there's nothing we need do here. */
725  if (OidIsValid(vrel->oid))
726  {
727  oldcontext = MemoryContextSwitchTo(vac_context);
728  vacrels = lappend(vacrels, vrel);
729  MemoryContextSwitchTo(oldcontext);
730  }
731  else
732  {
733  /* Process a specific relation, and possibly partitions thereof */
734  Oid relid;
735  HeapTuple tuple;
736  Form_pg_class classForm;
737  bool include_parts;
738  int rvr_opts;
739 
740  /*
741  * Since autovacuum workers supply OIDs when calling vacuum(), no
742  * autovacuum worker should reach this code.
743  */
745 
746  /*
747  * We transiently take AccessShareLock to protect the syscache lookup
748  * below, as well as find_all_inheritors's expectation that the caller
749  * holds some lock on the starting relation.
750  */
751  rvr_opts = (options & VACOPT_SKIP_LOCKED) ? RVR_SKIP_LOCKED : 0;
752  relid = RangeVarGetRelidExtended(vrel->relation,
754  rvr_opts,
755  NULL, NULL);
756 
757  /*
758  * If the lock is unavailable, emit the same log statement that
759  * vacuum_rel() and analyze_rel() would.
760  */
761  if (!OidIsValid(relid))
762  {
763  if (options & VACOPT_VACUUM)
765  (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
766  errmsg("skipping vacuum of \"%s\" --- lock not available",
767  vrel->relation->relname)));
768  else
770  (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
771  errmsg("skipping analyze of \"%s\" --- lock not available",
772  vrel->relation->relname)));
773  return vacrels;
774  }
775 
776  /*
777  * To check whether the relation is a partitioned table and its
778  * ownership, fetch its syscache entry.
779  */
780  tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
781  if (!HeapTupleIsValid(tuple))
782  elog(ERROR, "cache lookup failed for relation %u", relid);
783  classForm = (Form_pg_class) GETSTRUCT(tuple);
784 
785  /*
786  * Make a returnable VacuumRelation for this rel if user is a proper
787  * owner.
788  */
789  if (vacuum_is_relation_owner(relid, classForm, options))
790  {
791  oldcontext = MemoryContextSwitchTo(vac_context);
792  vacrels = lappend(vacrels, makeVacuumRelation(vrel->relation,
793  relid,
794  vrel->va_cols));
795  MemoryContextSwitchTo(oldcontext);
796  }
797 
798 
799  include_parts = (classForm->relkind == RELKIND_PARTITIONED_TABLE);
800  ReleaseSysCache(tuple);
801 
802  /*
803  * If it is, make relation list entries for its partitions. Note that
804  * the list returned by find_all_inheritors() includes the passed-in
805  * OID, so we have to skip that. There's no point in taking locks on
806  * the individual partitions yet, and doing so would just add
807  * unnecessary deadlock risk. For this last reason we do not check
808  * yet the ownership of the partitions, which get added to the list to
809  * process. Ownership will be checked later on anyway.
810  */
811  if (include_parts)
812  {
813  List *part_oids = find_all_inheritors(relid, NoLock, NULL);
814  ListCell *part_lc;
815 
816  foreach(part_lc, part_oids)
817  {
818  Oid part_oid = lfirst_oid(part_lc);
819 
820  if (part_oid == relid)
821  continue; /* ignore original table */
822 
823  /*
824  * We omit a RangeVar since it wouldn't be appropriate to
825  * complain about failure to open one of these relations
826  * later.
827  */
828  oldcontext = MemoryContextSwitchTo(vac_context);
829  vacrels = lappend(vacrels, makeVacuumRelation(NULL,
830  part_oid,
831  vrel->va_cols));
832  MemoryContextSwitchTo(oldcontext);
833  }
834  }
835 
836  /*
837  * Release lock again. This means that by the time we actually try to
838  * process the table, it might be gone or renamed. In the former case
839  * we'll silently ignore it; in the latter case we'll process it
840  * anyway, but we must beware that the RangeVar doesn't necessarily
841  * identify it anymore. This isn't ideal, perhaps, but there's little
842  * practical alternative, since we're typically going to commit this
843  * transaction and begin a new one between now and then. Moreover,
844  * holding locks on multiple relations would create significant risk
845  * of deadlock.
846  */
848  }
849 
850  return vacrels;
851 }
852 
853 /*
854  * Construct a list of VacuumRelations for all vacuumable rels in
855  * the current database. The list is built in vac_context.
856  */
857 static List *
859 {
860  List *vacrels = NIL;
861  Relation pgclass;
862  TableScanDesc scan;
863  HeapTuple tuple;
864 
865  pgclass = table_open(RelationRelationId, AccessShareLock);
866 
867  scan = table_beginscan_catalog(pgclass, 0, NULL);
868 
869  while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
870  {
871  Form_pg_class classForm = (Form_pg_class) GETSTRUCT(tuple);
872  MemoryContext oldcontext;
873  Oid relid = classForm->oid;
874 
875  /* check permissions of relation */
876  if (!vacuum_is_relation_owner(relid, classForm, options))
877  continue;
878 
879  /*
880  * We include partitioned tables here; depending on which operation is
881  * to be performed, caller will decide whether to process or ignore
882  * them.
883  */
884  if (classForm->relkind != RELKIND_RELATION &&
885  classForm->relkind != RELKIND_MATVIEW &&
886  classForm->relkind != RELKIND_PARTITIONED_TABLE)
887  continue;
888 
889  /*
890  * Build VacuumRelation(s) specifying the table OIDs to be processed.
891  * We omit a RangeVar since it wouldn't be appropriate to complain
892  * about failure to open one of these relations later.
893  */
894  oldcontext = MemoryContextSwitchTo(vac_context);
895  vacrels = lappend(vacrels, makeVacuumRelation(NULL,
896  relid,
897  NIL));
898  MemoryContextSwitchTo(oldcontext);
899  }
900 
901  table_endscan(scan);
902  table_close(pgclass, AccessShareLock);
903 
904  return vacrels;
905 }
906 
907 /*
908  * vacuum_set_xid_limits() -- compute oldestXmin and freeze cutoff points
909  *
910  * The output parameters are:
911  * - oldestXmin is the cutoff value used to distinguish whether tuples are
912  * DEAD or RECENTLY_DEAD (see HeapTupleSatisfiesVacuum).
913  * - freezeLimit is the Xid below which all Xids are replaced by
914  * FrozenTransactionId during vacuum.
915  * - xidFullScanLimit (computed from freeze_table_age parameter)
916  * represents a minimum Xid value; a table whose relfrozenxid is older than
917  * this will have a full-table vacuum applied to it, to freeze tuples across
918  * the whole table. Vacuuming a table younger than this value can use a
919  * partial scan.
920  * - multiXactCutoff is the value below which all MultiXactIds are removed from
921  * Xmax.
922  * - mxactFullScanLimit is a value against which a table's relminmxid value is
923  * compared to produce a full-table vacuum, as with xidFullScanLimit.
924  *
925  * xidFullScanLimit and mxactFullScanLimit can be passed as NULL if caller is
926  * not interested.
927  */
928 void
930  int freeze_min_age,
931  int freeze_table_age,
932  int multixact_freeze_min_age,
933  int multixact_freeze_table_age,
934  TransactionId *oldestXmin,
935  TransactionId *freezeLimit,
936  TransactionId *xidFullScanLimit,
937  MultiXactId *multiXactCutoff,
938  MultiXactId *mxactFullScanLimit)
939 {
940  int freezemin;
941  int mxid_freezemin;
942  int effective_multixact_freeze_max_age;
943  TransactionId limit;
944  TransactionId safeLimit;
945  MultiXactId oldestMxact;
946  MultiXactId mxactLimit;
947  MultiXactId safeMxactLimit;
948 
949  /*
950  * We can always ignore processes running lazy vacuum. This is because we
951  * use these values only for deciding which tuples we must keep in the
952  * tables. Since lazy vacuum doesn't write its XID anywhere, it's safe to
953  * ignore it. In theory it could be problematic to ignore lazy vacuums in
954  * a full vacuum, but keep in mind that only one vacuum process can be
955  * working on a particular table at any time, and that each vacuum is
956  * always an independent transaction.
957  */
958  *oldestXmin =
960 
961  Assert(TransactionIdIsNormal(*oldestXmin));
962 
963  /*
964  * Determine the minimum freeze age to use: as specified by the caller, or
965  * vacuum_freeze_min_age, but in any case not more than half
966  * autovacuum_freeze_max_age, so that autovacuums to prevent XID
967  * wraparound won't occur too frequently.
968  */
969  freezemin = freeze_min_age;
970  if (freezemin < 0)
971  freezemin = vacuum_freeze_min_age;
972  freezemin = Min(freezemin, autovacuum_freeze_max_age / 2);
973  Assert(freezemin >= 0);
974 
975  /*
976  * Compute the cutoff XID, being careful not to generate a "permanent" XID
977  */
978  limit = *oldestXmin - freezemin;
979  if (!TransactionIdIsNormal(limit))
980  limit = FirstNormalTransactionId;
981 
982  /*
983  * If oldestXmin is very far back (in practice, more than
984  * autovacuum_freeze_max_age / 2 XIDs old), complain and force a minimum
985  * freeze age of zero.
986  */
988  if (!TransactionIdIsNormal(safeLimit))
989  safeLimit = FirstNormalTransactionId;
990 
991  if (TransactionIdPrecedes(limit, safeLimit))
992  {
994  (errmsg("oldest xmin is far in the past"),
995  errhint("Close open transactions soon to avoid wraparound problems.\n"
996  "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
997  limit = *oldestXmin;
998  }
999 
1000  *freezeLimit = limit;
1001 
1002  /*
1003  * Compute the multixact age for which freezing is urgent. This is
1004  * normally autovacuum_multixact_freeze_max_age, but may be less if we are
1005  * short of multixact member space.
1006  */
1007  effective_multixact_freeze_max_age = MultiXactMemberFreezeThreshold();
1008 
1009  /*
1010  * Determine the minimum multixact freeze age to use: as specified by
1011  * caller, or vacuum_multixact_freeze_min_age, but in any case not more
1012  * than half effective_multixact_freeze_max_age, so that autovacuums to
1013  * prevent MultiXact wraparound won't occur too frequently.
1014  */
1015  mxid_freezemin = multixact_freeze_min_age;
1016  if (mxid_freezemin < 0)
1017  mxid_freezemin = vacuum_multixact_freeze_min_age;
1018  mxid_freezemin = Min(mxid_freezemin,
1019  effective_multixact_freeze_max_age / 2);
1020  Assert(mxid_freezemin >= 0);
1021 
1022  /* compute the cutoff multi, being careful to generate a valid value */
1023  oldestMxact = GetOldestMultiXactId();
1024  mxactLimit = oldestMxact - mxid_freezemin;
1025  if (mxactLimit < FirstMultiXactId)
1026  mxactLimit = FirstMultiXactId;
1027 
1028  safeMxactLimit =
1029  ReadNextMultiXactId() - effective_multixact_freeze_max_age;
1030  if (safeMxactLimit < FirstMultiXactId)
1031  safeMxactLimit = FirstMultiXactId;
1032 
1033  if (MultiXactIdPrecedes(mxactLimit, safeMxactLimit))
1034  {
1035  ereport(WARNING,
1036  (errmsg("oldest multixact is far in the past"),
1037  errhint("Close open transactions with multixacts soon to avoid wraparound problems.")));
1038  /* Use the safe limit, unless an older mxact is still running */
1039  if (MultiXactIdPrecedes(oldestMxact, safeMxactLimit))
1040  mxactLimit = oldestMxact;
1041  else
1042  mxactLimit = safeMxactLimit;
1043  }
1044 
1045  *multiXactCutoff = mxactLimit;
1046 
1047  if (xidFullScanLimit != NULL)
1048  {
1049  int freezetable;
1050 
1051  Assert(mxactFullScanLimit != NULL);
1052 
1053  /*
1054  * Determine the table freeze age to use: as specified by the caller,
1055  * or vacuum_freeze_table_age, but in any case not more than
1056  * autovacuum_freeze_max_age * 0.95, so that if you have e.g nightly
1057  * VACUUM schedule, the nightly VACUUM gets a chance to freeze tuples
1058  * before anti-wraparound autovacuum is launched.
1059  */
1060  freezetable = freeze_table_age;
1061  if (freezetable < 0)
1062  freezetable = vacuum_freeze_table_age;
1063  freezetable = Min(freezetable, autovacuum_freeze_max_age * 0.95);
1064  Assert(freezetable >= 0);
1065 
1066  /*
1067  * Compute XID limit causing a full-table vacuum, being careful not to
1068  * generate a "permanent" XID.
1069  */
1070  limit = ReadNewTransactionId() - freezetable;
1071  if (!TransactionIdIsNormal(limit))
1072  limit = FirstNormalTransactionId;
1073 
1074  *xidFullScanLimit = limit;
1075 
1076  /*
1077  * Similar to the above, determine the table freeze age to use for
1078  * multixacts: as specified by the caller, or
1079  * vacuum_multixact_freeze_table_age, but in any case not more than
1080  * autovacuum_multixact_freeze_table_age * 0.95, so that if you have
1081  * e.g. nightly VACUUM schedule, the nightly VACUUM gets a chance to
1082  * freeze multixacts before anti-wraparound autovacuum is launched.
1083  */
1084  freezetable = multixact_freeze_table_age;
1085  if (freezetable < 0)
1086  freezetable = vacuum_multixact_freeze_table_age;
1087  freezetable = Min(freezetable,
1088  effective_multixact_freeze_max_age * 0.95);
1089  Assert(freezetable >= 0);
1090 
1091  /*
1092  * Compute MultiXact limit causing a full-table vacuum, being careful
1093  * to generate a valid MultiXact value.
1094  */
1095  mxactLimit = ReadNextMultiXactId() - freezetable;
1096  if (mxactLimit < FirstMultiXactId)
1097  mxactLimit = FirstMultiXactId;
1098 
1099  *mxactFullScanLimit = mxactLimit;
1100  }
1101  else
1102  {
1103  Assert(mxactFullScanLimit == NULL);
1104  }
1105 }
1106 
1107 /*
1108  * vac_estimate_reltuples() -- estimate the new value for pg_class.reltuples
1109  *
1110  * If we scanned the whole relation then we should just use the count of
1111  * live tuples seen; but if we did not, we should not blindly extrapolate
1112  * from that number, since VACUUM may have scanned a quite nonrandom
1113  * subset of the table. When we have only partial information, we take
1114  * the old value of pg_class.reltuples as a measurement of the
1115  * tuple density in the unscanned pages.
1116  *
1117  * Note: scanned_tuples should count only *live* tuples, since
1118  * pg_class.reltuples is defined that way.
1119  */
1120 double
1122  BlockNumber total_pages,
1123  BlockNumber scanned_pages,
1124  double scanned_tuples)
1125 {
1126  BlockNumber old_rel_pages = relation->rd_rel->relpages;
1127  double old_rel_tuples = relation->rd_rel->reltuples;
1128  double old_density;
1129  double unscanned_pages;
1130  double total_tuples;
1131 
1132  /* If we did scan the whole table, just use the count as-is */
1133  if (scanned_pages >= total_pages)
1134  return scanned_tuples;
1135 
1136  /*
1137  * If scanned_pages is zero but total_pages isn't, keep the existing value
1138  * of reltuples. (Note: callers should avoid updating the pg_class
1139  * statistics in this situation, since no new information has been
1140  * provided.)
1141  */
1142  if (scanned_pages == 0)
1143  return old_rel_tuples;
1144 
1145  /*
1146  * If old value of relpages is zero, old density is indeterminate; we
1147  * can't do much except scale up scanned_tuples to match total_pages.
1148  */
1149  if (old_rel_pages == 0)
1150  return floor((scanned_tuples / scanned_pages) * total_pages + 0.5);
1151 
1152  /*
1153  * Okay, we've covered the corner cases. The normal calculation is to
1154  * convert the old measurement to a density (tuples per page), then
1155  * estimate the number of tuples in the unscanned pages using that figure,
1156  * and finally add on the number of tuples in the scanned pages.
1157  */
1158  old_density = old_rel_tuples / old_rel_pages;
1159  unscanned_pages = (double) total_pages - (double) scanned_pages;
1160  total_tuples = old_density * unscanned_pages + scanned_tuples;
1161  return floor(total_tuples + 0.5);
1162 }
1163 
1164 
1165 /*
1166  * vac_update_relstats() -- update statistics for one relation
1167  *
1168  * Update the whole-relation statistics that are kept in its pg_class
1169  * row. There are additional stats that will be updated if we are
1170  * doing ANALYZE, but we always update these stats. This routine works
1171  * for both index and heap relation entries in pg_class.
1172  *
1173  * We violate transaction semantics here by overwriting the rel's
1174  * existing pg_class tuple with the new values. This is reasonably
1175  * safe as long as we're sure that the new values are correct whether or
1176  * not this transaction commits. The reason for doing this is that if
1177  * we updated these tuples in the usual way, vacuuming pg_class itself
1178  * wouldn't work very well --- by the time we got done with a vacuum
1179  * cycle, most of the tuples in pg_class would've been obsoleted. Of
1180  * course, this only works for fixed-size not-null columns, but these are.
1181  *
1182  * Another reason for doing it this way is that when we are in a lazy
1183  * VACUUM and have PROC_IN_VACUUM set, we mustn't do any regular updates.
1184  * Somebody vacuuming pg_class might think they could delete a tuple
1185  * marked with xmin = our xid.
1186  *
1187  * In addition to fundamentally nontransactional statistics such as
1188  * relpages and relallvisible, we try to maintain certain lazily-updated
1189  * DDL flags such as relhasindex, by clearing them if no longer correct.
1190  * It's safe to do this in VACUUM, which can't run in parallel with
1191  * CREATE INDEX/RULE/TRIGGER and can't be part of a transaction block.
1192  * However, it's *not* safe to do it in an ANALYZE that's within an
1193  * outer transaction, because for example the current transaction might
1194  * have dropped the last index; then we'd think relhasindex should be
1195  * cleared, but if the transaction later rolls back this would be wrong.
1196  * So we refrain from updating the DDL flags if we're inside an outer
1197  * transaction. This is OK since postponing the flag maintenance is
1198  * always allowable.
1199  *
1200  * Note: num_tuples should count only *live* tuples, since
1201  * pg_class.reltuples is defined that way.
1202  *
1203  * This routine is shared by VACUUM and ANALYZE.
1204  */
1205 void
1207  BlockNumber num_pages, double num_tuples,
1208  BlockNumber num_all_visible_pages,
1209  bool hasindex, TransactionId frozenxid,
1210  MultiXactId minmulti,
1211  bool in_outer_xact)
1212 {
1213  Oid relid = RelationGetRelid(relation);
1214  Relation rd;
1215  HeapTuple ctup;
1216  Form_pg_class pgcform;
1217  bool dirty;
1218 
1219  rd = table_open(RelationRelationId, RowExclusiveLock);
1220 
1221  /* Fetch a copy of the tuple to scribble on */
1223  if (!HeapTupleIsValid(ctup))
1224  elog(ERROR, "pg_class entry for relid %u vanished during vacuuming",
1225  relid);
1226  pgcform = (Form_pg_class) GETSTRUCT(ctup);
1227 
1228  /* Apply statistical updates, if any, to copied tuple */
1229 
1230  dirty = false;
1231  if (pgcform->relpages != (int32) num_pages)
1232  {
1233  pgcform->relpages = (int32) num_pages;
1234  dirty = true;
1235  }
1236  if (pgcform->reltuples != (float4) num_tuples)
1237  {
1238  pgcform->reltuples = (float4) num_tuples;
1239  dirty = true;
1240  }
1241  if (pgcform->relallvisible != (int32) num_all_visible_pages)
1242  {
1243  pgcform->relallvisible = (int32) num_all_visible_pages;
1244  dirty = true;
1245  }
1246 
1247  /* Apply DDL updates, but not inside an outer transaction (see above) */
1248 
1249  if (!in_outer_xact)
1250  {
1251  /*
1252  * If we didn't find any indexes, reset relhasindex.
1253  */
1254  if (pgcform->relhasindex && !hasindex)
1255  {
1256  pgcform->relhasindex = false;
1257  dirty = true;
1258  }
1259 
1260  /* We also clear relhasrules and relhastriggers if needed */
1261  if (pgcform->relhasrules && relation->rd_rules == NULL)
1262  {
1263  pgcform->relhasrules = false;
1264  dirty = true;
1265  }
1266  if (pgcform->relhastriggers && relation->trigdesc == NULL)
1267  {
1268  pgcform->relhastriggers = false;
1269  dirty = true;
1270  }
1271  }
1272 
1273  /*
1274  * Update relfrozenxid, unless caller passed InvalidTransactionId
1275  * indicating it has no new data.
1276  *
1277  * Ordinarily, we don't let relfrozenxid go backwards: if things are
1278  * working correctly, the only way the new frozenxid could be older would
1279  * be if a previous VACUUM was done with a tighter freeze_min_age, in
1280  * which case we don't want to forget the work it already did. However,
1281  * if the stored relfrozenxid is "in the future", then it must be corrupt
1282  * and it seems best to overwrite it with the cutoff we used this time.
1283  * This should match vac_update_datfrozenxid() concerning what we consider
1284  * to be "in the future".
1285  */
1286  if (TransactionIdIsNormal(frozenxid) &&
1287  pgcform->relfrozenxid != frozenxid &&
1288  (TransactionIdPrecedes(pgcform->relfrozenxid, frozenxid) ||
1290  pgcform->relfrozenxid)))
1291  {
1292  pgcform->relfrozenxid = frozenxid;
1293  dirty = true;
1294  }
1295 
1296  /* Similarly for relminmxid */
1297  if (MultiXactIdIsValid(minmulti) &&
1298  pgcform->relminmxid != minmulti &&
1299  (MultiXactIdPrecedes(pgcform->relminmxid, minmulti) ||
1300  MultiXactIdPrecedes(ReadNextMultiXactId(), pgcform->relminmxid)))
1301  {
1302  pgcform->relminmxid = minmulti;
1303  dirty = true;
1304  }
1305 
1306  /* If anything changed, write out the tuple. */
1307  if (dirty)
1308  heap_inplace_update(rd, ctup);
1309 
1311 }
1312 
1313 
1314 /*
1315  * vac_update_datfrozenxid() -- update pg_database.datfrozenxid for our DB
1316  *
1317  * Update pg_database's datfrozenxid entry for our database to be the
1318  * minimum of the pg_class.relfrozenxid values.
1319  *
1320  * Similarly, update our datminmxid to be the minimum of the
1321  * pg_class.relminmxid values.
1322  *
1323  * If we are able to advance either pg_database value, also try to
1324  * truncate pg_xact and pg_multixact.
1325  *
1326  * We violate transaction semantics here by overwriting the database's
1327  * existing pg_database tuple with the new values. This is reasonably
1328  * safe since the new values are correct whether or not this transaction
1329  * commits. As with vac_update_relstats, this avoids leaving dead tuples
1330  * behind after a VACUUM.
1331  */
1332 void
1334 {
1335  HeapTuple tuple;
1336  Form_pg_database dbform;
1337  Relation relation;
1338  SysScanDesc scan;
1339  HeapTuple classTup;
1340  TransactionId newFrozenXid;
1341  MultiXactId newMinMulti;
1342  TransactionId lastSaneFrozenXid;
1343  MultiXactId lastSaneMinMulti;
1344  bool bogus = false;
1345  bool dirty = false;
1346 
1347  /*
1348  * Initialize the "min" calculation with GetOldestXmin, which is a
1349  * reasonable approximation to the minimum relfrozenxid for not-yet-
1350  * committed pg_class entries for new tables; see AddNewRelationTuple().
1351  * So we cannot produce a wrong minimum by starting with this.
1352  */
1353  newFrozenXid = GetOldestXmin(NULL, PROCARRAY_FLAGS_VACUUM);
1354 
1355  /*
1356  * Similarly, initialize the MultiXact "min" with the value that would be
1357  * used on pg_class for new tables. See AddNewRelationTuple().
1358  */
1359  newMinMulti = GetOldestMultiXactId();
1360 
1361  /*
1362  * Identify the latest relfrozenxid and relminmxid values that we could
1363  * validly see during the scan. These are conservative values, but it's
1364  * not really worth trying to be more exact.
1365  */
1366  lastSaneFrozenXid = ReadNewTransactionId();
1367  lastSaneMinMulti = ReadNextMultiXactId();
1368 
1369  /*
1370  * We must seqscan pg_class to find the minimum Xid, because there is no
1371  * index that can help us here.
1372  */
1373  relation = table_open(RelationRelationId, AccessShareLock);
1374 
1375  scan = systable_beginscan(relation, InvalidOid, false,
1376  NULL, 0, NULL);
1377 
1378  while ((classTup = systable_getnext(scan)) != NULL)
1379  {
1380  Form_pg_class classForm = (Form_pg_class) GETSTRUCT(classTup);
1381 
1382  /*
1383  * Only consider relations able to hold unfrozen XIDs (anything else
1384  * should have InvalidTransactionId in relfrozenxid anyway).
1385  */
1386  if (classForm->relkind != RELKIND_RELATION &&
1387  classForm->relkind != RELKIND_MATVIEW &&
1388  classForm->relkind != RELKIND_TOASTVALUE)
1389  {
1390  Assert(!TransactionIdIsValid(classForm->relfrozenxid));
1391  Assert(!MultiXactIdIsValid(classForm->relminmxid));
1392  continue;
1393  }
1394 
1395  /*
1396  * Some table AMs might not need per-relation xid / multixid horizons.
1397  * It therefore seems reasonable to allow relfrozenxid and relminmxid
1398  * to not be set (i.e. set to their respective Invalid*Id)
1399  * independently. Thus validate and compute horizon for each only if
1400  * set.
1401  *
1402  * If things are working properly, no relation should have a
1403  * relfrozenxid or relminmxid that is "in the future". However, such
1404  * cases have been known to arise due to bugs in pg_upgrade. If we
1405  * see any entries that are "in the future", chicken out and don't do
1406  * anything. This ensures we won't truncate clog & multixact SLRUs
1407  * before those relations have been scanned and cleaned up.
1408  */
1409 
1410  if (TransactionIdIsValid(classForm->relfrozenxid))
1411  {
1412  Assert(TransactionIdIsNormal(classForm->relfrozenxid));
1413 
1414  /* check for values in the future */
1415  if (TransactionIdPrecedes(lastSaneFrozenXid, classForm->relfrozenxid))
1416  {
1417  bogus = true;
1418  break;
1419  }
1420 
1421  /* determine new horizon */
1422  if (TransactionIdPrecedes(classForm->relfrozenxid, newFrozenXid))
1423  newFrozenXid = classForm->relfrozenxid;
1424  }
1425 
1426  if (MultiXactIdIsValid(classForm->relminmxid))
1427  {
1428  /* check for values in the future */
1429  if (MultiXactIdPrecedes(lastSaneMinMulti, classForm->relminmxid))
1430  {
1431  bogus = true;
1432  break;
1433  }
1434 
1435  /* determine new horizon */
1436  if (MultiXactIdPrecedes(classForm->relminmxid, newMinMulti))
1437  newMinMulti = classForm->relminmxid;
1438  }
1439  }
1440 
1441  /* we're done with pg_class */
1442  systable_endscan(scan);
1443  table_close(relation, AccessShareLock);
1444 
1445  /* chicken out if bogus data found */
1446  if (bogus)
1447  return;
1448 
1449  Assert(TransactionIdIsNormal(newFrozenXid));
1450  Assert(MultiXactIdIsValid(newMinMulti));
1451 
1452  /* Now fetch the pg_database tuple we need to update. */
1453  relation = table_open(DatabaseRelationId, RowExclusiveLock);
1454 
1455  /* Fetch a copy of the tuple to scribble on */
1457  if (!HeapTupleIsValid(tuple))
1458  elog(ERROR, "could not find tuple for database %u", MyDatabaseId);
1459  dbform = (Form_pg_database) GETSTRUCT(tuple);
1460 
1461  /*
1462  * As in vac_update_relstats(), we ordinarily don't want to let
1463  * datfrozenxid go backward; but if it's "in the future" then it must be
1464  * corrupt and it seems best to overwrite it.
1465  */
1466  if (dbform->datfrozenxid != newFrozenXid &&
1467  (TransactionIdPrecedes(dbform->datfrozenxid, newFrozenXid) ||
1468  TransactionIdPrecedes(lastSaneFrozenXid, dbform->datfrozenxid)))
1469  {
1470  dbform->datfrozenxid = newFrozenXid;
1471  dirty = true;
1472  }
1473  else
1474  newFrozenXid = dbform->datfrozenxid;
1475 
1476  /* Ditto for datminmxid */
1477  if (dbform->datminmxid != newMinMulti &&
1478  (MultiXactIdPrecedes(dbform->datminmxid, newMinMulti) ||
1479  MultiXactIdPrecedes(lastSaneMinMulti, dbform->datminmxid)))
1480  {
1481  dbform->datminmxid = newMinMulti;
1482  dirty = true;
1483  }
1484  else
1485  newMinMulti = dbform->datminmxid;
1486 
1487  if (dirty)
1488  heap_inplace_update(relation, tuple);
1489 
1490  heap_freetuple(tuple);
1491  table_close(relation, RowExclusiveLock);
1492 
1493  /*
1494  * If we were able to advance datfrozenxid or datminmxid, see if we can
1495  * truncate pg_xact and/or pg_multixact. Also do it if the shared
1496  * XID-wrap-limit info is stale, since this action will update that too.
1497  */
1498  if (dirty || ForceTransactionIdLimitUpdate())
1499  vac_truncate_clog(newFrozenXid, newMinMulti,
1500  lastSaneFrozenXid, lastSaneMinMulti);
1501 }
1502 
1503 
1504 /*
1505  * vac_truncate_clog() -- attempt to truncate the commit log
1506  *
1507  * Scan pg_database to determine the system-wide oldest datfrozenxid,
1508  * and use it to truncate the transaction commit log (pg_xact).
1509  * Also update the XID wrap limit info maintained by varsup.c.
1510  * Likewise for datminmxid.
1511  *
1512  * The passed frozenXID and minMulti are the updated values for my own
1513  * pg_database entry. They're used to initialize the "min" calculations.
1514  * The caller also passes the "last sane" XID and MXID, since it has
1515  * those at hand already.
1516  *
1517  * This routine is only invoked when we've managed to change our
1518  * DB's datfrozenxid/datminmxid values, or we found that the shared
1519  * XID-wrap-limit info is stale.
1520  */
1521 static void
1523  MultiXactId minMulti,
1524  TransactionId lastSaneFrozenXid,
1525  MultiXactId lastSaneMinMulti)
1526 {
1527  TransactionId nextXID = ReadNewTransactionId();
1528  Relation relation;
1529  TableScanDesc scan;
1530  HeapTuple tuple;
1531  Oid oldestxid_datoid;
1532  Oid minmulti_datoid;
1533  bool bogus = false;
1534  bool frozenAlreadyWrapped = false;
1535 
1536  /* init oldest datoids to sync with my frozenXID/minMulti values */
1537  oldestxid_datoid = MyDatabaseId;
1538  minmulti_datoid = MyDatabaseId;
1539 
1540  /*
1541  * Scan pg_database to compute the minimum datfrozenxid/datminmxid
1542  *
1543  * Since vac_update_datfrozenxid updates datfrozenxid/datminmxid in-place,
1544  * the values could change while we look at them. Fetch each one just
1545  * once to ensure sane behavior of the comparison logic. (Here, as in
1546  * many other places, we assume that fetching or updating an XID in shared
1547  * storage is atomic.)
1548  *
1549  * Note: we need not worry about a race condition with new entries being
1550  * inserted by CREATE DATABASE. Any such entry will have a copy of some
1551  * existing DB's datfrozenxid, and that source DB cannot be ours because
1552  * of the interlock against copying a DB containing an active backend.
1553  * Hence the new entry will not reduce the minimum. Also, if two VACUUMs
1554  * concurrently modify the datfrozenxid's of different databases, the
1555  * worst possible outcome is that pg_xact is not truncated as aggressively
1556  * as it could be.
1557  */
1558  relation = table_open(DatabaseRelationId, AccessShareLock);
1559 
1560  scan = table_beginscan_catalog(relation, 0, NULL);
1561 
1562  while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
1563  {
1564  volatile FormData_pg_database *dbform = (Form_pg_database) GETSTRUCT(tuple);
1565  TransactionId datfrozenxid = dbform->datfrozenxid;
1566  TransactionId datminmxid = dbform->datminmxid;
1567 
1568  Assert(TransactionIdIsNormal(datfrozenxid));
1569  Assert(MultiXactIdIsValid(datminmxid));
1570 
1571  /*
1572  * If things are working properly, no database should have a
1573  * datfrozenxid or datminmxid that is "in the future". However, such
1574  * cases have been known to arise due to bugs in pg_upgrade. If we
1575  * see any entries that are "in the future", chicken out and don't do
1576  * anything. This ensures we won't truncate clog before those
1577  * databases have been scanned and cleaned up. (We will issue the
1578  * "already wrapped" warning if appropriate, though.)
1579  */
1580  if (TransactionIdPrecedes(lastSaneFrozenXid, datfrozenxid) ||
1581  MultiXactIdPrecedes(lastSaneMinMulti, datminmxid))
1582  bogus = true;
1583 
1584  if (TransactionIdPrecedes(nextXID, datfrozenxid))
1585  frozenAlreadyWrapped = true;
1586  else if (TransactionIdPrecedes(datfrozenxid, frozenXID))
1587  {
1588  frozenXID = datfrozenxid;
1589  oldestxid_datoid = dbform->oid;
1590  }
1591 
1592  if (MultiXactIdPrecedes(datminmxid, minMulti))
1593  {
1594  minMulti = datminmxid;
1595  minmulti_datoid = dbform->oid;
1596  }
1597  }
1598 
1599  table_endscan(scan);
1600 
1601  table_close(relation, AccessShareLock);
1602 
1603  /*
1604  * Do not truncate CLOG if we seem to have suffered wraparound already;
1605  * the computed minimum XID might be bogus. This case should now be
1606  * impossible due to the defenses in GetNewTransactionId, but we keep the
1607  * test anyway.
1608  */
1609  if (frozenAlreadyWrapped)
1610  {
1611  ereport(WARNING,
1612  (errmsg("some databases have not been vacuumed in over 2 billion transactions"),
1613  errdetail("You might have already suffered transaction-wraparound data loss.")));
1614  return;
1615  }
1616 
1617  /* chicken out if data is bogus in any other way */
1618  if (bogus)
1619  return;
1620 
1621  /*
1622  * Advance the oldest value for commit timestamps before truncating, so
1623  * that if a user requests a timestamp for a transaction we're truncating
1624  * away right after this point, they get NULL instead of an ugly "file not
1625  * found" error from slru.c. This doesn't matter for xact/multixact
1626  * because they are not subject to arbitrary lookups from users.
1627  */
1628  AdvanceOldestCommitTsXid(frozenXID);
1629 
1630  /*
1631  * Truncate CLOG, multixact and CommitTs to the oldest computed value.
1632  */
1633  TruncateCLOG(frozenXID, oldestxid_datoid);
1634  TruncateCommitTs(frozenXID);
1635  TruncateMultiXact(minMulti, minmulti_datoid);
1636 
1637  /*
1638  * Update the wrap limit for GetNewTransactionId and creation of new
1639  * MultiXactIds. Note: these functions will also signal the postmaster
1640  * for an(other) autovac cycle if needed. XXX should we avoid possibly
1641  * signaling twice?
1642  */
1643  SetTransactionIdLimit(frozenXID, oldestxid_datoid);
1644  SetMultiXactIdLimit(minMulti, minmulti_datoid, false);
1645 }
1646 
1647 
1648 /*
1649  * vacuum_rel() -- vacuum one heap relation
1650  *
1651  * relid identifies the relation to vacuum. If relation is supplied,
1652  * use the name therein for reporting any failure to open/lock the rel;
1653  * do not use it once we've successfully opened the rel, since it might
1654  * be stale.
1655  *
1656  * Returns true if it's okay to proceed with a requested ANALYZE
1657  * operation on this table.
1658  *
1659  * Doing one heap at a time incurs extra overhead, since we need to
1660  * check that the heap exists again just before we vacuum it. The
1661  * reason that we do this is so that vacuuming can be spread across
1662  * many small transactions. Otherwise, two-phase locking would require
1663  * us to lock the entire database during one pass of the vacuum cleaner.
1664  *
1665  * At entry and exit, we are not inside a transaction.
1666  */
1667 static bool
1668 vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params)
1669 {
1670  LOCKMODE lmode;
1671  Relation onerel;
1672  LockRelId onerelid;
1673  Oid toast_relid;
1674  Oid save_userid;
1675  int save_sec_context;
1676  int save_nestlevel;
1677 
1678  Assert(params != NULL);
1679 
1680  /* Begin a transaction for vacuuming this relation */
1682 
1683  /*
1684  * Functions in indexes may want a snapshot set. Also, setting a snapshot
1685  * ensures that RecentGlobalXmin is kept truly recent.
1686  */
1688 
1689  if (!(params->options & VACOPT_FULL))
1690  {
1691  /*
1692  * In lazy vacuum, we can set the PROC_IN_VACUUM flag, which lets
1693  * other concurrent VACUUMs know that they can ignore this one while
1694  * determining their OldestXmin. (The reason we don't set it during a
1695  * full VACUUM is exactly that we may have to run user-defined
1696  * functions for functional indexes, and we want to make sure that if
1697  * they use the snapshot set above, any tuples it requires can't get
1698  * removed from other tables. An index function that depends on the
1699  * contents of other tables is arguably broken, but we won't break it
1700  * here by violating transaction semantics.)
1701  *
1702  * We also set the VACUUM_FOR_WRAPAROUND flag, which is passed down by
1703  * autovacuum; it's used to avoid canceling a vacuum that was invoked
1704  * in an emergency.
1705  *
1706  * Note: these flags remain set until CommitTransaction or
1707  * AbortTransaction. We don't want to clear them until we reset
1708  * MyPgXact->xid/xmin, else OldestXmin might appear to go backwards,
1709  * which is probably Not Good.
1710  */
1711  LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
1713  if (params->is_wraparound)
1715  LWLockRelease(ProcArrayLock);
1716  }
1717 
1718  /*
1719  * Check for user-requested abort. Note we want this to be inside a
1720  * transaction, so xact.c doesn't issue useless WARNING.
1721  */
1723 
1724  /*
1725  * Determine the type of lock we want --- hard exclusive lock for a FULL
1726  * vacuum, but just ShareUpdateExclusiveLock for concurrent vacuum. Either
1727  * way, we can be sure that no other backend is vacuuming the same table.
1728  */
1729  lmode = (params->options & VACOPT_FULL) ?
1731 
1732  /* open the relation and get the appropriate lock on it */
1733  onerel = vacuum_open_relation(relid, relation, params->options,
1734  params->log_min_duration >= 0, lmode);
1735 
1736  /* leave if relation could not be opened or locked */
1737  if (!onerel)
1738  {
1741  return false;
1742  }
1743 
1744  /*
1745  * Check if relation needs to be skipped based on ownership. This check
1746  * happens also when building the relation list to vacuum for a manual
1747  * operation, and needs to be done additionally here as VACUUM could
1748  * happen across multiple transactions where relation ownership could have
1749  * changed in-between. Make sure to only generate logs for VACUUM in this
1750  * case.
1751  */
1753  onerel->rd_rel,
1754  params->options & VACOPT_VACUUM))
1755  {
1756  relation_close(onerel, lmode);
1759  return false;
1760  }
1761 
1762  /*
1763  * Check that it's of a vacuumable relkind.
1764  */
1765  if (onerel->rd_rel->relkind != RELKIND_RELATION &&
1766  onerel->rd_rel->relkind != RELKIND_MATVIEW &&
1767  onerel->rd_rel->relkind != RELKIND_TOASTVALUE &&
1768  onerel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
1769  {
1770  ereport(WARNING,
1771  (errmsg("skipping \"%s\" --- cannot vacuum non-tables or special system tables",
1772  RelationGetRelationName(onerel))));
1773  relation_close(onerel, lmode);
1776  return false;
1777  }
1778 
1779  /*
1780  * Silently ignore tables that are temp tables of other backends ---
1781  * trying to vacuum these will lead to great unhappiness, since their
1782  * contents are probably not up-to-date on disk. (We don't throw a
1783  * warning here; it would just lead to chatter during a database-wide
1784  * VACUUM.)
1785  */
1786  if (RELATION_IS_OTHER_TEMP(onerel))
1787  {
1788  relation_close(onerel, lmode);
1791  return false;
1792  }
1793 
1794  /*
1795  * Silently ignore partitioned tables as there is no work to be done. The
1796  * useful work is on their child partitions, which have been queued up for
1797  * us separately.
1798  */
1799  if (onerel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
1800  {
1801  relation_close(onerel, lmode);
1804  /* It's OK to proceed with ANALYZE on this table */
1805  return true;
1806  }
1807 
1808  /*
1809  * Get a session-level lock too. This will protect our access to the
1810  * relation across multiple transactions, so that we can vacuum the
1811  * relation's TOAST table (if any) secure in the knowledge that no one is
1812  * deleting the parent relation.
1813  *
1814  * NOTE: this cannot block, even if someone else is waiting for access,
1815  * because the lock manager knows that both lock requests are from the
1816  * same process.
1817  */
1818  onerelid = onerel->rd_lockInfo.lockRelId;
1819  LockRelationIdForSession(&onerelid, lmode);
1820 
1821  /* Set index cleanup option based on reloptions if not yet */
1822  if (params->index_cleanup == VACOPT_TERNARY_DEFAULT)
1823  {
1824  if (onerel->rd_options == NULL ||
1825  ((StdRdOptions *) onerel->rd_options)->vacuum_index_cleanup)
1827  else
1829  }
1830 
1831  /* Set truncate option based on reloptions if not yet */
1832  if (params->truncate == VACOPT_TERNARY_DEFAULT)
1833  {
1834  if (onerel->rd_options == NULL ||
1835  ((StdRdOptions *) onerel->rd_options)->vacuum_truncate)
1836  params->truncate = VACOPT_TERNARY_ENABLED;
1837  else
1839  }
1840 
1841  /*
1842  * Remember the relation's TOAST relation for later, if the caller asked
1843  * us to process it. In VACUUM FULL, though, the toast table is
1844  * automatically rebuilt by cluster_rel so we shouldn't recurse to it.
1845  */
1846  if (!(params->options & VACOPT_SKIPTOAST) && !(params->options & VACOPT_FULL))
1847  toast_relid = onerel->rd_rel->reltoastrelid;
1848  else
1849  toast_relid = InvalidOid;
1850 
1851  /*
1852  * Switch to the table owner's userid, so that any index functions are run
1853  * as that user. Also lock down security-restricted operations and
1854  * arrange to make GUC variable changes local to this command. (This is
1855  * unnecessary, but harmless, for lazy VACUUM.)
1856  */
1857  GetUserIdAndSecContext(&save_userid, &save_sec_context);
1858  SetUserIdAndSecContext(onerel->rd_rel->relowner,
1859  save_sec_context | SECURITY_RESTRICTED_OPERATION);
1860  save_nestlevel = NewGUCNestLevel();
1861 
1862  /*
1863  * Do the actual work --- either FULL or "lazy" vacuum
1864  */
1865  if (params->options & VACOPT_FULL)
1866  {
1867  int cluster_options = 0;
1868 
1869  /* close relation before vacuuming, but hold lock until commit */
1870  relation_close(onerel, NoLock);
1871  onerel = NULL;
1872 
1873  if ((params->options & VACOPT_VERBOSE) != 0)
1874  cluster_options |= CLUOPT_VERBOSE;
1875 
1876  /* VACUUM FULL is now a variant of CLUSTER; see cluster.c */
1877  cluster_rel(relid, InvalidOid, cluster_options);
1878  }
1879  else
1880  table_relation_vacuum(onerel, params, vac_strategy);
1881 
1882  /* Roll back any GUC changes executed by index functions */
1883  AtEOXact_GUC(false, save_nestlevel);
1884 
1885  /* Restore userid and security context */
1886  SetUserIdAndSecContext(save_userid, save_sec_context);
1887 
1888  /* all done with this class, but hold lock until commit */
1889  if (onerel)
1890  relation_close(onerel, NoLock);
1891 
1892  /*
1893  * Complete the transaction and free all temporary memory used.
1894  */
1897 
1898  /*
1899  * If the relation has a secondary toast rel, vacuum that too while we
1900  * still hold the session lock on the main table. Note however that
1901  * "analyze" will not get done on the toast table. This is good, because
1902  * the toaster always uses hardcoded index access and statistics are
1903  * totally unimportant for toast relations.
1904  */
1905  if (toast_relid != InvalidOid)
1906  vacuum_rel(toast_relid, NULL, params);
1907 
1908  /*
1909  * Now release the session-level lock on the main table.
1910  */
1911  UnlockRelationIdForSession(&onerelid, lmode);
1912 
1913  /* Report that we really did it. */
1914  return true;
1915 }
1916 
1917 
1918 /*
1919  * Open all the vacuumable indexes of the given relation, obtaining the
1920  * specified kind of lock on each. Return an array of Relation pointers for
1921  * the indexes into *Irel, and the number of indexes into *nindexes.
1922  *
1923  * We consider an index vacuumable if it is marked insertable (indisready).
1924  * If it isn't, probably a CREATE INDEX CONCURRENTLY command failed early in
1925  * execution, and what we have is too corrupt to be processable. We will
1926  * vacuum even if the index isn't indisvalid; this is important because in a
1927  * unique index, uniqueness checks will be performed anyway and had better not
1928  * hit dangling index pointers.
1929  */
1930 void
1932  int *nindexes, Relation **Irel)
1933 {
1934  List *indexoidlist;
1935  ListCell *indexoidscan;
1936  int i;
1937 
1938  Assert(lockmode != NoLock);
1939 
1940  indexoidlist = RelationGetIndexList(relation);
1941 
1942  /* allocate enough memory for all indexes */
1943  i = list_length(indexoidlist);
1944 
1945  if (i > 0)
1946  *Irel = (Relation *) palloc(i * sizeof(Relation));
1947  else
1948  *Irel = NULL;
1949 
1950  /* collect just the ready indexes */
1951  i = 0;
1952  foreach(indexoidscan, indexoidlist)
1953  {
1954  Oid indexoid = lfirst_oid(indexoidscan);
1955  Relation indrel;
1956 
1957  indrel = index_open(indexoid, lockmode);
1958  if (indrel->rd_index->indisready)
1959  (*Irel)[i++] = indrel;
1960  else
1961  index_close(indrel, lockmode);
1962  }
1963 
1964  *nindexes = i;
1965 
1966  list_free(indexoidlist);
1967 }
1968 
1969 /*
1970  * Release the resources acquired by vac_open_indexes. Optionally release
1971  * the locks (say NoLock to keep 'em).
1972  */
1973 void
1974 vac_close_indexes(int nindexes, Relation *Irel, LOCKMODE lockmode)
1975 {
1976  if (Irel == NULL)
1977  return;
1978 
1979  while (nindexes--)
1980  {
1981  Relation ind = Irel[nindexes];
1982 
1983  index_close(ind, lockmode);
1984  }
1985  pfree(Irel);
1986 }
1987 
1988 /*
1989  * vacuum_delay_point --- check for interrupts and cost-based delay.
1990  *
1991  * This should be called in each major loop of VACUUM processing,
1992  * typically once per page processed.
1993  */
1994 void
1996 {
1997  double msec = 0;
1998 
1999  /* Always check for interrupts */
2001 
2003  return;
2004 
2005  /*
2006  * For parallel vacuum, the delay is computed based on the shared cost
2007  * balance. See compute_parallel_delay.
2008  */
2009  if (VacuumSharedCostBalance != NULL)
2010  msec = compute_parallel_delay();
2011  else if (VacuumCostBalance >= VacuumCostLimit)
2013 
2014  /* Nap if appropriate */
2015  if (msec > 0)
2016  {
2017  if (msec > VacuumCostDelay * 4)
2018  msec = VacuumCostDelay * 4;
2019 
2021  pg_usleep((long) (msec * 1000));
2023 
2024  VacuumCostBalance = 0;
2025 
2026  /* update balance values for workers */
2028 
2029  /* Might have gotten an interrupt while sleeping */
2031  }
2032 }
2033 
2034 /*
2035  * Computes the vacuum delay for parallel workers.
2036  *
2037  * The basic idea of a cost-based delay for parallel vacuum is to allow each
2038  * worker to sleep in proportion to the share of work it's done. We achieve this
2039  * by allowing all parallel vacuum workers including the leader process to
2040  * have a shared view of cost related parameters (mainly VacuumCostBalance).
2041  * We allow each worker to update it as and when it has incurred any cost and
2042  * then based on that decide whether it needs to sleep. We compute the time
2043  * to sleep for a worker based on the cost it has incurred
2044  * (VacuumCostBalanceLocal) and then reduce the VacuumSharedCostBalance by
2045  * that amount. This avoids putting to sleep those workers which have done less
2046  * I/O than other workers and therefore ensure that workers
2047  * which are doing more I/O got throttled more.
2048  *
2049  * We allow a worker to sleep only if it has performed I/O above a certain
2050  * threshold, which is calculated based on the number of active workers
2051  * (VacuumActiveNWorkers), and the overall cost balance is more than
2052  * VacuumCostLimit set by the system. Testing reveals that we achieve
2053  * the required throttling if we force a worker that has done more than 50%
2054  * of its share of work to sleep.
2055  */
2056 static double
2058 {
2059  double msec = 0;
2060  uint32 shared_balance;
2061  int nworkers;
2062 
2063  /* Parallel vacuum must be active */
2064  Assert(VacuumSharedCostBalance);
2065 
2066  nworkers = pg_atomic_read_u32(VacuumActiveNWorkers);
2067 
2068  /* At least count itself */
2069  Assert(nworkers >= 1);
2070 
2071  /* Update the shared cost balance value atomically */
2072  shared_balance = pg_atomic_add_fetch_u32(VacuumSharedCostBalance, VacuumCostBalance);
2073 
2074  /* Compute the total local balance for the current worker */
2076 
2077  if ((shared_balance >= VacuumCostLimit) &&
2078  (VacuumCostBalanceLocal > 0.5 * ((double) VacuumCostLimit / nworkers)))
2079  {
2080  /* Compute sleep time based on the local cost balance */
2082  pg_atomic_sub_fetch_u32(VacuumSharedCostBalance, VacuumCostBalanceLocal);
2084  }
2085 
2086  /*
2087  * Reset the local balance as we accumulated it into the shared value.
2088  */
2089  VacuumCostBalance = 0;
2090 
2091  return msec;
2092 }
2093 
2094 /*
2095  * A wrapper function of defGetBoolean().
2096  *
2097  * This function returns VACOPT_TERNARY_ENABLED and VACOPT_TERNARY_DISABLED
2098  * instead of true and false.
2099  */
2100 static VacOptTernaryValue
2102 {
2104 }
BufferAccessStrategy GetAccessStrategy(BufferAccessStrategyType btype)
Definition: freelist.c:542
#define NIL
Definition: pg_list.h:65
bool ConditionalLockRelationOid(Oid relid, LOCKMODE lockmode)
Definition: lmgr.c:151
void analyze_rel(Oid relid, RangeVar *relation, VacuumParams *params, List *va_cols, bool in_outer_xact, BufferAccessStrategy bstrategy)
Definition: analyze.c:119
static double compute_parallel_delay(void)
Definition: vacuum.c:2057
int multixact_freeze_table_age
Definition: vacuum.h:215
void vac_close_indexes(int nindexes, Relation *Irel, LOCKMODE lockmode)
Definition: vacuum.c:1974
LockRelId lockRelId
Definition: rel.h:44
void vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy, bool isTopLevel)
Definition: vacuum.c:272
void MemoryContextDelete(MemoryContext context)
Definition: mcxt.c:211
#define AllocSetContextCreate
Definition: memutils.h:170
int64 VacuumPageMiss
Definition: globals.c:145
void table_close(Relation relation, LOCKMODE lockmode)
Definition: table.c:133
int errhint(const char *fmt,...)
Definition: elog.c:1071
void systable_endscan(SysScanDesc sysscan)
Definition: genam.c:569
#define GETSTRUCT(TUP)
Definition: htup_details.h:655
#define ERRCODE_UNDEFINED_TABLE
Definition: pgbench.c:73
pg_atomic_uint32 * VacuumActiveNWorkers
Definition: vacuum.c:77
double vac_estimate_reltuples(Relation relation, BlockNumber total_pages, BlockNumber scanned_pages, double scanned_tuples)
Definition: vacuum.c:1121
int VacuumCostBalance
Definition: globals.c:148
int vacuum_multixact_freeze_table_age
Definition: vacuum.c:64
void TruncateCLOG(TransactionId oldestXact, Oid oldestxid_datoid)
Definition: clog.c:899
static bool vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params)
Definition: vacuum.c:1668
RangeVar * relation
Definition: parsenodes.h:3240
uint32 TransactionId
Definition: c.h:520
#define SECURITY_RESTRICTED_OPERATION
Definition: miscadmin.h:299
TableScanDesc table_beginscan_catalog(Relation relation, int nkeys, struct ScanKeyData *key)
Definition: tableam.c:112
void vac_update_datfrozenxid(void)
Definition: vacuum.c:1333
void SetUserIdAndSecContext(Oid userid, int sec_context)
Definition: miscinit.c:562
int LOCKMODE
Definition: lockdefs.h:26
Oid GetUserId(void)
Definition: miscinit.c:450
void UnlockRelationOid(Oid relid, LOCKMODE lockmode)
Definition: lmgr.c:199
FormData_pg_database * Form_pg_database
Definition: pg_database.h:81
VacuumRelation * makeVacuumRelation(RangeVar *relation, Oid oid, List *va_cols)
Definition: makefuncs.c:808
static uint32 pg_atomic_sub_fetch_u32(volatile pg_atomic_uint32 *ptr, int32 sub_)
Definition: atomics.h:401
void CommitTransactionCommand(void)
Definition: xact.c:2947
int64 VacuumPageHit
Definition: globals.c:144
#define Min(x, y)
Definition: c.h:927
TransactionId TransactionIdLimitedForOldSnapshots(TransactionId recentXmin, Relation relation)
Definition: snapmgr.c:1775
bool is_vacuumcmd
Definition: parsenodes.h:3227
#define PROC_VACUUM_FOR_WRAPAROUND
Definition: proc.h:55
static MemoryContext MemoryContextSwitchTo(MemoryContext context)
Definition: palloc.h:109
static void table_relation_vacuum(Relation rel, struct VacuumParams *params, BufferAccessStrategy bstrategy)
Definition: tableam.h:1482
#define AccessShareLock
Definition: lockdefs.h:36
static BufferAccessStrategy vac_strategy
Definition: vacuum.c:69
int32 defGetInt32(DefElem *def)
Definition: define.c:166
struct cursor * cur
Definition: ecpg.c:28
List * list_concat(List *list1, const List *list2)
Definition: list.c:515
int errcode(int sqlerrcode)
Definition: elog.c:610
static uint32 pg_atomic_add_fetch_u32(volatile pg_atomic_uint32 *ptr, int32 add_)
Definition: atomics.h:386
void vacuum_set_xid_limits(Relation rel, int freeze_min_age, int freeze_table_age, int multixact_freeze_min_age, int multixact_freeze_table_age, TransactionId *oldestXmin, TransactionId *freezeLimit, TransactionId *xidFullScanLimit, MultiXactId *multiXactCutoff, MultiXactId *mxactFullScanLimit)
Definition: vacuum.c:929
int64 VacuumPageDirty
Definition: globals.c:146
uint32 BlockNumber
Definition: block.h:31
VacOptTernaryValue
Definition: vacuum.h:195
void PopActiveSnapshot(void)
Definition: snapmgr.c:814
#define PROCARRAY_FLAGS_VACUUM
Definition: procarray.h:49
#define LOG
Definition: elog.h:26
Form_pg_class rd_rel
Definition: rel.h:109
void heap_freetuple(HeapTuple htup)
Definition: heaptuple.c:1338
NameData relname
Definition: pg_class.h:38
unsigned int Oid
Definition: postgres_ext.h:31
Snapshot GetTransactionSnapshot(void)
Definition: snapmgr.c:306
#define OidIsValid(objectId)
Definition: c.h:651
void AdvanceOldestCommitTsXid(TransactionId oldestXact)
Definition: commit_ts.c:936
int freeze_table_age
Definition: vacuum.h:212
SysScanDesc systable_beginscan(Relation heapRelation, Oid indexId, bool indexOK, Snapshot snapshot, int nkeys, ScanKey key)
Definition: genam.c:357
void cluster_rel(Oid tableOid, Oid indexOid, int options)
Definition: cluster.c:253
Relation try_relation_open(Oid relationId, LOCKMODE lockmode)
Definition: relation.c:89
signed int int32
Definition: c.h:362
static List * expand_vacuum_rel(VacuumRelation *vrel, int options)
Definition: vacuum.c:719
PGXACT * MyPgXact
Definition: proc.c:68
uint8 vacuumFlags
Definition: proc.h:239
MemoryContext PortalContext
Definition: mcxt.c:53
void LWLockRelease(LWLock *lock)
Definition: lwlock.c:1812
bool ForceTransactionIdLimitUpdate(void)
Definition: varsup.c:474
char * relname
Definition: primnodes.h:68
void pg_usleep(long microsec)
Definition: signal.c:53
bool defGetBoolean(DefElem *def)
Definition: define.c:111
Form_pg_index rd_index
Definition: rel.h:174
HeapTuple systable_getnext(SysScanDesc sysscan)
Definition: genam.c:476
void pfree(void *pointer)
Definition: mcxt.c:1056
#define PROC_IN_VACUUM
Definition: proc.h:54
#define FirstNormalTransactionId
Definition: transam.h:34
void UnlockRelationIdForSession(LockRelId *relid, LOCKMODE lockmode)
Definition: lmgr.c:382
#define ObjectIdGetDatum(X)
Definition: postgres.h:507
#define ERROR
Definition: elog.h:43
Definition: rel.h:36
int VacuumCostLimit
Definition: globals.c:141
void LockRelationIdForSession(LockRelId *relid, LOCKMODE lockmode)
Definition: lmgr.c:369
int autovacuum_freeze_max_age
Definition: autovacuum.c:124
int freeze_min_age
Definition: vacuum.h:211
int vacuum_multixact_freeze_min_age
Definition: vacuum.c:63
TriggerDesc * trigdesc
Definition: rel.h:115
#define ALLOCSET_DEFAULT_SIZES
Definition: memutils.h:192
bool is_wraparound
Definition: vacuum.h:217
#define lfirst_node(type, lc)
Definition: pg_list.h:193
bool vacuum_is_relation_owner(Oid relid, Form_pg_class reltuple, int options)
Definition: vacuum.c:533
#define NoLock
Definition: lockdefs.h:34
LockInfoData rd_lockInfo
Definition: rel.h:112
HeapTuple heap_getnext(TableScanDesc sscan, ScanDirection direction)
Definition: heapam.c:1286
void PushActiveSnapshot(Snapshot snap)
Definition: snapmgr.c:735
Relation vacuum_open_relation(Oid relid, RangeVar *relation, int options, bool verbose, LOCKMODE lmode)
Definition: vacuum.c:607
void GetUserIdAndSecContext(Oid *userid, int *sec_context)
Definition: miscinit.c:555
int location
Definition: parsenodes.h:735
#define RowExclusiveLock
Definition: lockdefs.h:38
void AtEOXact_GUC(bool isCommit, int nestLevel)
Definition: guc.c:5956
int errdetail(const char *fmt,...)
Definition: elog.c:957
static MemoryContext vac_context
Definition: vacuum.c:68
void PreventInTransactionBlock(bool isTopLevel, const char *stmtType)
Definition: xact.c:3380
#define RelationGetRelationName(relation)
Definition: rel.h:490
Oid RangeVarGetRelidExtended(const RangeVar *relation, LOCKMODE lockmode, uint32 flags, RangeVarGetRelidCallback callback, void *callback_arg)
Definition: namespace.c:236
unsigned int uint32
Definition: c.h:374
#define MultiXactIdIsValid(multi)
Definition: multixact.h:27
bool ActiveSnapshotSet(void)
Definition: snapmgr.c:853
static void pgstat_report_wait_end(void)
Definition: pgstat.h:1381
#define FirstMultiXactId
Definition: multixact.h:24
bool IsAutoVacuumWorkerProcess(void)
Definition: autovacuum.c:3301
void pgstat_vacuum_stat(void)
Definition: pgstat.c:1052
int MultiXactMemberFreezeThreshold(void)
Definition: multixact.c:2815
bool pg_database_ownercheck(Oid db_oid, Oid roleid)
Definition: aclchk.c:5105
bool TransactionIdPrecedes(TransactionId id1, TransactionId id2)
Definition: transam.c:300
void TruncateCommitTs(TransactionId oldestXact)
Definition: commit_ts.c:883
VacOptTernaryValue index_cleanup
Definition: vacuum.h:221
Node * arg
Definition: parsenodes.h:733
List * lappend(List *list, void *datum)
Definition: list.c:321
bool IsInTransactionBlock(bool isTopLevel)
Definition: xact.c:3493
static int verbose
#define WARNING
Definition: elog.h:40
void vac_open_indexes(Relation relation, LOCKMODE lockmode, int *nindexes, Relation **Irel)
Definition: vacuum.c:1931
HeapTuple SearchSysCache1(int cacheId, Datum key1)
Definition: syscache.c:1116
float float4
Definition: c.h:497
int VacuumCostBalanceLocal
Definition: vacuum.c:78
pg_atomic_uint32 * VacuumSharedCostBalance
Definition: vacuum.c:76
static int elevel
Definition: vacuumlazy.c:330
#define PG_FINALLY()
Definition: elog.h:312
MultiXactId GetOldestMultiXactId(void)
Definition: multixact.c:2489
void CommandCounterIncrement(void)
Definition: xact.c:1021
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:1164
Oid MyDatabaseId
Definition: globals.c:85
void SetMultiXactIdLimit(MultiXactId oldest_datminmxid, Oid oldest_datoid, bool is_startup)
Definition: multixact.c:2196
#define InvalidOid
Definition: postgres_ext.h:36
VacOptTernaryValue truncate
Definition: vacuum.h:223
TransactionId datfrozenxid
Definition: pg_database.h:62
#define ereport(elevel,...)
Definition: elog.h:144
TransactionId GetOldestXmin(Relation rel, int flags)
Definition: procarray.c:1359
TransactionId MultiXactId
Definition: c.h:530
#define ShareUpdateExclusiveLock
Definition: lockdefs.h:39
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
void ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
Definition: vacuum.c:98
void relation_close(Relation relation, LOCKMODE lockmode)
Definition: relation.c:206
#define Assert(condition)
Definition: c.h:745
#define lfirst(lc)
Definition: pg_list.h:190
#define RELATION_IS_OTHER_TEMP(relation)
Definition: rel.h:593
bool pg_class_ownercheck(Oid class_oid, Oid roleid)
Definition: aclchk.c:4687
void StartTransactionCommand(void)
Definition: xact.c:2846
RuleLock * rd_rules
Definition: rel.h:113
static void pgstat_report_wait_start(uint32 wait_event_info)
Definition: pgstat.h:1357
void SetTransactionIdLimit(TransactionId oldest_datfrozenxid, Oid oldest_datoid)
Definition: varsup.c:330
int nworkers
Definition: vacuum.h:231
static int list_length(const List *l)
Definition: pg_list.h:169
int parser_errposition(ParseState *pstate, int location)
Definition: parse_node.c:110
bool LWLockAcquire(LWLock *lock, LWLockMode mode)
Definition: lwlock.c:1208
int vacuum_freeze_min_age
Definition: vacuum.c:61
TransactionId datminmxid
Definition: pg_database.h:65
int log_min_duration
Definition: vacuum.h:218
volatile sig_atomic_t InterruptPending
Definition: globals.c:30
bool MultiXactIdPrecedes(MultiXactId multi1, MultiXactId multi2)
Definition: multixact.c:3138
static void vac_truncate_clog(TransactionId frozenXID, MultiXactId minMulti, TransactionId lastSaneFrozenXid, MultiXactId lastSaneMinMulti)
Definition: vacuum.c:1522
List * RelationGetIndexList(Relation relation)
Definition: relcache.c:4507
int vacuum_freeze_table_age
Definition: vacuum.c:62
void index_close(Relation relation, LOCKMODE lockmode)
Definition: indexam.c:158
static TransactionId ReadNewTransactionId(void)
Definition: transam.h:291
static void table_endscan(TableScanDesc scan)
Definition: tableam.h:863
FormData_pg_class * Form_pg_class
Definition: pg_class.h:153
#define SearchSysCacheCopy1(cacheId, key1)
Definition: syscache.h:174
#define AccessExclusiveLock
Definition: lockdefs.h:45
List * find_all_inheritors(Oid parentrelId, LOCKMODE lockmode, List **numparents)
Definition: pg_inherits.c:165
int NewGUCNestLevel(void)
Definition: guc.c:5942
void * palloc(Size size)
Definition: mcxt.c:949
int errmsg(const char *fmt,...)
Definition: elog.c:824
void heap_inplace_update(Relation relation, HeapTuple tuple)
Definition: heapam.c:5710
double VacuumCostDelay
Definition: globals.c:142
List * options
Definition: parsenodes.h:3225
void list_free(List *list)
Definition: list.c:1376
#define elog(elevel,...)
Definition: elog.h:214
int i
int options
Definition: vacuum.h:210
#define NameStr(name)
Definition: c.h:622
void AutoVacuumUpdateDelay(void)
Definition: autovacuum.c:1759
FormData_pg_database
Definition: pg_database.h:74
char * defname
Definition: parsenodes.h:732
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:99
#define TransactionIdIsValid(xid)
Definition: transam.h:41
#define MAX_PARALLEL_WORKER_LIMIT
void vacuum_delay_point(void)
Definition: vacuum.c:1995
#define TransactionIdIsNormal(xid)
Definition: transam.h:42
#define PG_TRY()
Definition: elog.h:295
void TruncateMultiXact(MultiXactId newOldestMulti, Oid newOldestMultiDB)
Definition: multixact.c:2931
Relation table_open(Oid relationId, LOCKMODE lockmode)
Definition: table.c:39
void vac_update_relstats(Relation relation, BlockNumber num_pages, double num_tuples, BlockNumber num_all_visible_pages, bool hasindex, TransactionId frozenxid, MultiXactId minmulti, bool in_outer_xact)
Definition: vacuum.c:1206
Definition: pg_list.h:50
#define RelationGetRelid(relation)
Definition: rel.h:456
int multixact_freeze_min_age
Definition: vacuum.h:213
static long analyze(struct nfa *nfa)
Definition: regc_nfa.c:2816
Relation index_open(Oid relationId, LOCKMODE lockmode)
Definition: indexam.c:132
#define PG_END_TRY()
Definition: elog.h:320
bytea * rd_options
Definition: rel.h:157
#define lfirst_oid(lc)
Definition: pg_list.h:192
bool VacuumCostActive
Definition: globals.c:149
static List * get_all_vacuum_rels(int options)
Definition: vacuum.c:858
static uint32 pg_atomic_read_u32(volatile pg_atomic_uint32 *ptr)
Definition: atomics.h:241
MultiXactId ReadNextMultiXactId(void)
Definition: multixact.c:723
List * rels
Definition: parsenodes.h:3226
static VacOptTernaryValue get_vacopt_ternary_value(DefElem *def)
Definition: vacuum.c:2101