From d611f8b1587b8f30caa7c0da99ae5d28e914d54f Mon Sep 17 00:00:00 2001 From: Jeff Davis Date: Thu, 6 Mar 2025 19:36:34 -0800 Subject: CREATE INDEX: don't update table stats if autovacuum=off. We previously fixed this for binary upgrade in 71b66171d0, but a similar problem remained when dumping statistics without data. Fix by not opportunistically updating table stats during CREATE INDEX when autovacuum is disabled. For stats to be stable at all, the server needs to be aware that it should not take every opportunity to update stats. Per discussion, autovacuum=off is a signal that the user expects stats to be stable; though if necessary, we could create a more specific mode in the future. Reported-by: Ashutosh Bapat Discussion: https://postgr.es/m/CAExHW5vf9D+8-a5_BEX3y=2y_xY9hiCxV1=C+FnxDvfprWvkng@mail.gmail.com Discussion: https://postgr.es/m/ca81cbf6e6ea2af838df972801ad4da52640a503.camel%40j-davis.com --- src/backend/catalog/index.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'src/backend') diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c index 8e1741c81f5..022b9b99b13 100644 --- a/src/backend/catalog/index.c +++ b/src/backend/catalog/index.c @@ -63,6 +63,7 @@ #include "optimizer/optimizer.h" #include "parser/parser.h" #include "pgstat.h" +#include "postmaster/autovacuum.h" #include "rewrite/rewriteManip.h" #include "storage/bufmgr.h" #include "storage/lmgr.h" @@ -2840,6 +2841,27 @@ index_update_stats(Relation rel, */ update_stats = reltuples >= 0 && !IsBinaryUpgrade; + /* + * If autovacuum is off, user may not be expecting table relstats to + * change. This can be important when restoring a dump that includes + * statistics, as the table statistics may be restored before the index is + * created, and we want to preserve the restored table statistics. + */ + if (AutoVacuumingActive()) + { + if (rel->rd_rel->relkind == RELKIND_RELATION || + rel->rd_rel->relkind == RELKIND_TOASTVALUE || + rel->rd_rel->relkind == RELKIND_MATVIEW) + { + StdRdOptions *options = (StdRdOptions *) rel->rd_options; + + if (options != NULL && !options->autovacuum.enabled) + update_stats = false; + } + } + else + update_stats = false; + /* * Finish I/O and visibility map buffer locks before * systable_inplace_update_begin() locks the pg_class buffer. The rd_rel -- cgit v1.2.3