From ad337c76b6f454157982309089c3302fe77c9cbc Mon Sep 17 00:00:00 2001 From: Teodor Sigaev Date: Wed, 27 Dec 2017 18:25:37 +0300 Subject: [PATCH] Update relation's stats in pg_class during vacuum full. Hash index depends on estimation of numbers of tuples and pages of relations, incorrect value could be a reason of significantly growing of index. Vacuum full recreates heap and reindex all indexes before renewal stats. The patch fixes that, so indexes will see correct values. Backpatch to v10 only because earlier versions haven't usable hash index and growing of hash index is a single user-visible symptom. Author: Amit Kapila Reviewed-by: Ashutosh Sharma, me Discussion: https://www.postgresql.org/message-id/flat/20171115232922.5tomkxnw3iq6jsg7@inml.weebeastie.net --- src/backend/commands/cluster.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 48f1e6e2ad..1c5669afa8 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -738,6 +738,9 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex, bool verbose, Relation NewHeap, OldHeap, OldIndex; + Relation relRelation; + HeapTuple reltup; + Form_pg_class relform; TupleDesc oldTupDesc; TupleDesc newTupDesc; int natts; @@ -756,6 +759,7 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex, bool verbose, double num_tuples = 0, tups_vacuumed = 0, tups_recently_dead = 0; + BlockNumber num_pages; int elevel = verbose ? INFO : DEBUG2; PGRUsage ru0; @@ -1079,6 +1083,8 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex, bool verbose, /* Reset rd_toastoid just to be tidy --- it shouldn't be looked at again */ NewHeap->rd_toastoid = InvalidOid; + num_pages = RelationGetNumberOfBlocks(NewHeap); + /* Log what we did */ ereport(elevel, (errmsg("\"%s\": found %.0f removable, %.0f nonremovable row versions in %u pages", @@ -1098,6 +1104,30 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex, bool verbose, index_close(OldIndex, NoLock); heap_close(OldHeap, NoLock); heap_close(NewHeap, NoLock); + + /* Update pg_class to reflect the correct values of pages and tuples. */ + relRelation = heap_open(RelationRelationId, RowExclusiveLock); + + reltup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(OIDNewHeap)); + if (!HeapTupleIsValid(reltup)) + elog(ERROR, "cache lookup failed for relation %u", OIDNewHeap); + relform = (Form_pg_class) GETSTRUCT(reltup); + + relform->relpages = num_pages; + relform->reltuples = num_tuples; + + /* Don't update the stats for pg_class. See swap_relation_files. */ + if (OIDOldHeap != RelationRelationId) + CatalogTupleUpdate(relRelation, &reltup->t_self, reltup); + else + CacheInvalidateRelcacheByTuple(reltup); + + /* Clean up. */ + heap_freetuple(reltup); + heap_close(relRelation, RowExclusiveLock); + + /* Make the update visible */ + CommandCounterIncrement(); } /* -- 2.40.0