*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/postmaster/autovacuum.c,v 1.39 2007/03/27 20:36:03 alvherre Exp $
+ * $PostgreSQL: pgsql/src/backend/postmaster/autovacuum.c,v 1.40 2007/03/28 22:17:12 alvherre Exp $
*
*-------------------------------------------------------------------------
*/
PgStat_StatDBEntry *ad_entry;
} autovac_dbase;
+/* struct to keep track of tables to vacuum and/or analyze, in 1st pass */
+typedef struct av_relation
+{
+ Oid ar_relid;
+ Oid ar_toastrelid;
+} av_relation;
+
/* struct to keep track of tables to vacuum and/or analyze, after rechecking */
typedef struct autovac_table
{
NON_EXEC_STATIC void AutoVacLauncherMain(int argc, char *argv[]);
static void do_start_worker(void);
-static void do_autovacuum(Oid dbid);
+static void do_autovacuum(void);
static List *autovac_get_database_list(void);
-static void test_rel_for_autovac(Oid relid, PgStat_StatTabEntry *tabentry,
- Form_pg_class classForm,
- Form_pg_autovacuum avForm,
- List **vacuum_tables,
- List **toast_table_ids);
+
+static void relation_check_autovac(Oid relid, Form_pg_class classForm,
+ Form_pg_autovacuum avForm, PgStat_StatTabEntry *tabentry,
+ List **table_oids, List **table_toast_list,
+ List **toast_oids);
+static autovac_table *table_recheck_autovac(Oid relid);
+static void relation_needs_vacanalyze(Oid relid, Form_pg_autovacuum avForm,
+ Form_pg_class classForm,
+ PgStat_StatTabEntry *tabentry, bool *dovacuum,
+ bool *doanalyze);
+
static void autovacuum_do_vac_analyze(Oid relid, bool dovacuum,
bool doanalyze, int freeze_min_age);
static HeapTuple get_pg_autovacuum_tuple_relid(Relation avRel, Oid relid);
/* And do an appropriate amount of work */
recentXid = ReadNewTransactionId();
- do_autovacuum(dbid);
+ do_autovacuum();
}
/*
* order not to ignore shutdown commands for too long.
*/
static void
-do_autovacuum(Oid dbid)
+do_autovacuum(void)
{
Relation classRel,
avRel;
HeapTuple tuple;
HeapScanDesc relScan;
Form_pg_database dbForm;
- List *vacuum_tables = NIL;
- List *toast_table_ids = NIL;
+ List *table_oids = NIL;
+ List *toast_oids = NIL;
+ List *table_toast_list = NIL;
ListCell *cell;
PgStat_StatDBEntry *shared;
PgStat_StatDBEntry *dbentry;
* may be NULL if we couldn't find an entry (only happens if we
* are forcing a vacuum for anti-wrap purposes).
*/
- dbentry = pgstat_fetch_stat_dbentry(dbid);
+ dbentry = pgstat_fetch_stat_dbentry(MyDatabaseId);
/* Start a transaction so our commands have one to play into. */
StartTransactionCommand();
tabentry = get_pgstat_tabentry_relid(relid, classForm->relisshared,
shared, dbentry);
- test_rel_for_autovac(relid, tabentry, classForm, avForm,
- &vacuum_tables, &toast_table_ids);
+ relation_check_autovac(relid, classForm, avForm, tabentry,
+ &table_oids, &table_toast_list, &toast_oids);
if (HeapTupleIsValid(avTup))
heap_freetuple(avTup);
heap_close(classRel, AccessShareLock);
/*
+ * Add to the list of tables to vacuum, the OIDs of the tables that
+ * correspond to the saved OIDs of toast tables needing vacuum.
+ */
+ foreach (cell, toast_oids)
+ {
+ Oid toastoid = lfirst_oid(cell);
+ ListCell *cell2;
+
+ foreach (cell2, table_toast_list)
+ {
+ av_relation *ar = lfirst(cell2);
+
+ if (ar->ar_toastrelid == toastoid)
+ {
+ table_oids = lappend_oid(table_oids, ar->ar_relid);
+ break;
+ }
+ }
+ }
+
+ list_free_deep(table_toast_list);
+ table_toast_list = NIL;
+ list_free(toast_oids);
+ toast_oids = NIL;
+
+ /*
* Perform operations on collected tables.
*/
- foreach(cell, vacuum_tables)
+ foreach(cell, table_oids)
{
- autovac_table *tab = lfirst(cell);
+ Oid relid = lfirst_oid(cell);
+ autovac_table *tab;
+ char *relname;
CHECK_FOR_INTERRUPTS();
/*
- * Check to see if we need to force vacuuming of this table because
- * its toast table needs it.
+ * Check whether pgstat data still says we need to vacuum this table.
+ * It could have changed if something else processed the table while we
+ * weren't looking.
+ *
+ * FIXME we ignore the possibility that the table was finished being
+ * vacuumed in the last 500ms (PGSTAT_STAT_INTERVAL). This is a bug.
*/
- if (OidIsValid(tab->at_toastrelid) && !tab->at_dovacuum &&
- list_member_oid(toast_table_ids, tab->at_toastrelid))
+ tab = table_recheck_autovac(relid);
+ if (tab == NULL)
{
- tab->at_dovacuum = true;
- elog(DEBUG2, "autovac: VACUUM %u because of TOAST table",
- tab->at_relid);
- }
-
- /* Otherwise, ignore table if it needs no work */
- if (!tab->at_dovacuum && !tab->at_doanalyze)
+ /* someone else vacuumed the table */
continue;
+ }
+ /* Ok, good to go! */
/* Set the vacuum cost parameters for this table */
VacuumCostDelay = tab->at_vacuum_cost_delay;
VacuumCostLimit = tab->at_vacuum_cost_limit;
+ relname = get_rel_name(relid);
+ elog(DEBUG2, "autovac: will%s%s %s",
+ (tab->at_dovacuum ? " VACUUM" : ""),
+ (tab->at_doanalyze ? " ANALYZE" : ""),
+ relname);
+
autovacuum_do_vac_analyze(tab->at_relid,
tab->at_dovacuum,
tab->at_doanalyze,
tab->at_freeze_min_age);
+ /* be tidy */
+ pfree(tab);
+ pfree(relname);
}
/*
}
/*
- * test_rel_for_autovac
+ * relation_check_autovac
*
- * Check whether a table needs to be vacuumed or analyzed. Add it to the
- * appropriate output list if so.
+ * For a given relation (either a plain table or TOAST table), check whether it
+ * needs vacuum or analyze.
+ *
+ * Plain tables that need either are added to the table_list. TOAST tables
+ * that need vacuum are added to toast_list. Plain tables that don't need
+ * either but which have a TOAST table are added, as a struct, to
+ * table_toast_list. The latter is to allow appending the OIDs of the plain
+ * tables whose TOAST table needs vacuuming into the plain tables list, which
+ * allows us to substantially reduce the number of "rechecks" that we need to
+ * do later on.
+ */
+static void
+relation_check_autovac(Oid relid, Form_pg_class classForm,
+ Form_pg_autovacuum avForm, PgStat_StatTabEntry *tabentry,
+ List **table_oids, List **table_toast_list,
+ List **toast_oids)
+{
+ bool dovacuum;
+ bool doanalyze;
+
+ relation_needs_vacanalyze(relid, avForm, classForm, tabentry,
+ &dovacuum, &doanalyze);
+
+ if (classForm->relkind == RELKIND_TOASTVALUE)
+ {
+ if (dovacuum)
+ *toast_oids = lappend_oid(*toast_oids, relid);
+ }
+ else
+ {
+ Assert(classForm->relkind == RELKIND_RELATION);
+
+ if (dovacuum || doanalyze)
+ *table_oids = lappend_oid(*table_oids, relid);
+ else if (OidIsValid(classForm->reltoastrelid))
+ {
+ av_relation *rel = palloc(sizeof(av_relation));
+
+ rel->ar_relid = relid;
+ rel->ar_toastrelid = classForm->reltoastrelid;
+
+ *table_toast_list = lappend(*table_toast_list, rel);
+ }
+ }
+}
+
+/*
+ * table_recheck_autovac
+ *
+ * Recheck whether a plain table still needs vacuum or analyze; be it because
+ * it does directly, or because its TOAST table does. Return value is a valid
+ * autovac_table pointer if it does, NULL otherwise.
+ */
+static autovac_table *
+table_recheck_autovac(Oid relid)
+{
+ Form_pg_autovacuum avForm = NULL;
+ Form_pg_class classForm;
+ HeapTuple classTup;
+ HeapTuple avTup;
+ Relation avRel;
+ bool dovacuum;
+ bool doanalyze;
+ autovac_table *tab = NULL;
+ PgStat_StatTabEntry *tabentry;
+ bool doit = false;
+ PgStat_StatDBEntry *shared;
+ PgStat_StatDBEntry *dbentry;
+
+ /* We need fresh pgstat data for this */
+ pgstat_clear_snapshot();
+
+ shared = pgstat_fetch_stat_dbentry(InvalidOid);
+ dbentry = pgstat_fetch_stat_dbentry(MyDatabaseId);
+
+ /* fetch the relation's relcache entry */
+ classTup = SearchSysCacheCopy(RELOID,
+ ObjectIdGetDatum(relid),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(classTup))
+ return NULL;
+ classForm = (Form_pg_class) GETSTRUCT(classTup);
+
+ /* fetch the pg_autovacuum entry, if any */
+ avRel = heap_open(AutovacuumRelationId, AccessShareLock);
+ avTup = get_pg_autovacuum_tuple_relid(avRel, relid);
+ if (HeapTupleIsValid(avTup))
+ avForm = (Form_pg_autovacuum) GETSTRUCT(avTup);
+
+ /* fetch the pgstat table entry */
+ tabentry = get_pgstat_tabentry_relid(relid, classForm->relisshared,
+ shared, dbentry);
+
+ relation_needs_vacanalyze(relid, avForm, classForm, tabentry,
+ &dovacuum, &doanalyze);
+
+ /* OK, it needs vacuum by itself */
+ if (dovacuum)
+ doit = true;
+ /* it doesn't need vacuum, but what about it's TOAST table? */
+ else if (OidIsValid(classForm->reltoastrelid))
+ {
+ Oid toastrelid = classForm->reltoastrelid;
+ HeapTuple toastClassTup;
+
+ toastClassTup = SearchSysCacheCopy(RELOID,
+ ObjectIdGetDatum(toastrelid),
+ 0, 0, 0);
+ if (HeapTupleIsValid(toastClassTup))
+ {
+ bool toast_dovacuum;
+ bool toast_doanalyze;
+ Form_pg_class toastClassForm;
+ PgStat_StatTabEntry *toasttabentry;
+
+ toastClassForm = (Form_pg_class) GETSTRUCT(toastClassTup);
+ toasttabentry = get_pgstat_tabentry_relid(toastrelid,
+ toastClassForm->relisshared,
+ shared, dbentry);
+
+ /* note we use the pg_autovacuum entry for the main table */
+ relation_needs_vacanalyze(toastrelid, avForm, toastClassForm,
+ toasttabentry, &toast_dovacuum,
+ &toast_doanalyze);
+ /* we only consider VACUUM for toast tables */
+ if (toast_dovacuum)
+ {
+ dovacuum = true;
+ doit = true;
+ }
+
+ heap_freetuple(toastClassTup);
+ }
+ }
+
+ if (doanalyze)
+ doit = true;
+
+ if (doit)
+ {
+ int freeze_min_age;
+ int vac_cost_limit;
+ int vac_cost_delay;
+
+ /*
+ * Calculate the vacuum cost parameters and the minimum freeze age. If
+ * there is a tuple in pg_autovacuum, use it; else, use the GUC
+ * defaults. Note that the fields may contain "-1" (or indeed any
+ * negative value), which means use the GUC defaults for each setting.
+ */
+ if (avForm != NULL)
+ {
+ vac_cost_limit = (avForm->vac_cost_limit >= 0) ?
+ avForm->vac_cost_limit :
+ ((autovacuum_vac_cost_limit >= 0) ?
+ autovacuum_vac_cost_limit : VacuumCostLimit);
+
+ vac_cost_delay = (avForm->vac_cost_delay >= 0) ?
+ avForm->vac_cost_delay :
+ ((autovacuum_vac_cost_delay >= 0) ?
+ autovacuum_vac_cost_delay : VacuumCostDelay);
+
+ freeze_min_age = (avForm->freeze_min_age >= 0) ?
+ avForm->freeze_min_age : default_freeze_min_age;
+ }
+ else
+ {
+ vac_cost_limit = (autovacuum_vac_cost_limit >= 0) ?
+ autovacuum_vac_cost_limit : VacuumCostLimit;
+
+ vac_cost_delay = (autovacuum_vac_cost_delay >= 0) ?
+ autovacuum_vac_cost_delay : VacuumCostDelay;
+
+ freeze_min_age = default_freeze_min_age;
+ }
+
+ tab = palloc(sizeof(autovac_table));
+ tab->at_relid = relid;
+ tab->at_dovacuum = dovacuum;
+ tab->at_doanalyze = doanalyze;
+ tab->at_freeze_min_age = freeze_min_age;
+ tab->at_vacuum_cost_limit = vac_cost_limit;
+ tab->at_vacuum_cost_delay = vac_cost_delay;
+ }
+
+ heap_close(avRel, AccessShareLock);
+ if (HeapTupleIsValid(avTup))
+ heap_freetuple(avTup);
+ heap_freetuple(classTup);
+
+ return tab;
+}
+
+/*
+ * relation_needs_vacanalyze
+ *
+ * Check whether a relation needs to be vacuumed or analyzed; return each into
+ * "dovacuum" and "doanalyze", respectively. avForm and tabentry can be NULL,
+ * classForm shouldn't.
*
* A table needs to be vacuumed if the number of dead tuples exceeds a
* threshold. This threshold is calculated as
* autovacuum_vacuum_scale_factor GUC variable. Ditto for analyze.
*/
static void
-test_rel_for_autovac(Oid relid, PgStat_StatTabEntry *tabentry,
- Form_pg_class classForm,
- Form_pg_autovacuum avForm,
- List **vacuum_tables,
- List **toast_table_ids)
+relation_needs_vacanalyze(Oid relid,
+ Form_pg_autovacuum avForm,
+ Form_pg_class classForm,
+ PgStat_StatTabEntry *tabentry,
+ /* output params below */
+ bool *dovacuum,
+ bool *doanalyze)
{
bool force_vacuum;
- bool dovacuum;
- bool doanalyze;
float4 reltuples; /* pg_class.reltuples */
/* constants from pg_autovacuum or GUC variables */
int vac_base_thresh,
float4 vactuples,
anltuples;
/* freeze parameters */
- int freeze_min_age;
int freeze_max_age;
TransactionId xidForceLimit;
- /* cost-based vacuum delay parameters */
- int vac_cost_limit;
- int vac_cost_delay;
+
+ AssertArg(classForm != NULL);
+ AssertArg(OidIsValid(relid));
/*
- * If there is a tuple in pg_autovacuum, use it; else, use the GUC
- * defaults. Note that the fields may contain "-1" (or indeed any
- * negative value), which means use the GUC defaults for each setting.
+ * Determine vacuum/analyze equation parameters. If there is a tuple in
+ * pg_autovacuum, use it; else, use the GUC defaults. Note that the fields
+ * may contain "-1" (or indeed any negative value), which means use the GUC
+ * defaults for each setting.
*/
if (avForm != NULL)
{
anl_base_thresh = (avForm->anl_base_thresh >= 0) ?
avForm->anl_base_thresh : autovacuum_anl_thresh;
- freeze_min_age = (avForm->freeze_min_age >= 0) ?
- avForm->freeze_min_age : default_freeze_min_age;
freeze_max_age = (avForm->freeze_max_age >= 0) ?
Min(avForm->freeze_max_age, autovacuum_freeze_max_age) :
autovacuum_freeze_max_age;
-
- vac_cost_limit = (avForm->vac_cost_limit >= 0) ?
- avForm->vac_cost_limit :
- ((autovacuum_vac_cost_limit >= 0) ?
- autovacuum_vac_cost_limit : VacuumCostLimit);
-
- vac_cost_delay = (avForm->vac_cost_delay >= 0) ?
- avForm->vac_cost_delay :
- ((autovacuum_vac_cost_delay >= 0) ?
- autovacuum_vac_cost_delay : VacuumCostDelay);
}
else
{
anl_scale_factor = autovacuum_anl_scale;
anl_base_thresh = autovacuum_anl_thresh;
- freeze_min_age = default_freeze_min_age;
freeze_max_age = autovacuum_freeze_max_age;
-
- vac_cost_limit = (autovacuum_vac_cost_limit >= 0) ?
- autovacuum_vac_cost_limit : VacuumCostLimit;
-
- vac_cost_delay = (autovacuum_vac_cost_delay >= 0) ?
- autovacuum_vac_cost_delay : VacuumCostDelay;
}
/* Force vacuum if table is at risk of wraparound */
/* User disabled it in pg_autovacuum? (But ignore if at risk) */
if (avForm && !avForm->enabled && !force_vacuum)
+ {
+ *doanalyze = false;
+ *dovacuum = false;
return;
+ }
if (PointerIsValid(tabentry))
{
vactuples, vacthresh, anltuples, anlthresh);
/* Determine if this table needs vacuum or analyze. */
- dovacuum = force_vacuum || (vactuples > vacthresh);
- doanalyze = (anltuples > anlthresh);
+ *dovacuum = force_vacuum || (vactuples > vacthresh);
+ *doanalyze = (anltuples > anlthresh);
}
else
{
* vacuum for anti-wrap purposes. If it's not acted upon, there's
* no need to vacuum it.
*/
- dovacuum = force_vacuum;
- doanalyze = false;
+ *dovacuum = force_vacuum;
+ *doanalyze = false;
}
/* ANALYZE refuses to work with pg_statistics */
if (relid == StatisticRelationId)
- doanalyze = false;
-
- Assert(CurrentMemoryContext == AutovacMemCxt);
-
- if (classForm->relkind == RELKIND_RELATION)
- {
- if (dovacuum || doanalyze)
- elog(DEBUG2, "autovac: will%s%s %s",
- (dovacuum ? " VACUUM" : ""),
- (doanalyze ? " ANALYZE" : ""),
- NameStr(classForm->relname));
-
- /*
- * we must record tables that have a toast table, even if we currently
- * don't think they need vacuuming.
- */
- if (dovacuum || doanalyze || OidIsValid(classForm->reltoastrelid))
- {
- autovac_table *tab;
-
- tab = (autovac_table *) palloc(sizeof(autovac_table));
- tab->at_relid = relid;
- tab->at_toastrelid = classForm->reltoastrelid;
- tab->at_dovacuum = dovacuum;
- tab->at_doanalyze = doanalyze;
- tab->at_freeze_min_age = freeze_min_age;
- tab->at_vacuum_cost_limit = vac_cost_limit;
- tab->at_vacuum_cost_delay = vac_cost_delay;
-
- *vacuum_tables = lappend(*vacuum_tables, tab);
- }
- }
- else
- {
- Assert(classForm->relkind == RELKIND_TOASTVALUE);
- if (dovacuum)
- *toast_table_ids = lappend_oid(*toast_table_ids, relid);
- }
+ *doanalyze = false;
}
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