From 5acc58c5e5336d16a1e238e8f1d599e8bfa4183b Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Mon, 6 Jun 2016 17:44:17 -0400 Subject: [PATCH] Don't reset changes_since_analyze after a selective-columns ANALYZE. If we ANALYZE only selected columns of a table, we should not postpone auto-analyze because of that; other columns may well still need stats updates. As committed, the counter is left alone if a column list is given, whether or not it includes all analyzable columns of the table. Per complaint from Tomasz Ostrowski. It's been like this a long time, so back-patch to all supported branches. Report: --- src/backend/commands/analyze.c | 7 +++++-- src/backend/postmaster/pgstat.c | 15 +++++++++++---- src/include/pgstat.h | 4 +++- 3 files changed, 19 insertions(+), 7 deletions(-) diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c index ddb68abf6b..04b08b6377 100644 --- a/src/backend/commands/analyze.c +++ b/src/backend/commands/analyze.c @@ -605,10 +605,13 @@ do_analyze_rel(Relation onerel, int options, VacuumParams *params, /* * Report ANALYZE to the stats collector, too. However, if doing * inherited stats we shouldn't report, because the stats collector only - * tracks per-table stats. + * tracks per-table stats. Reset the changes_since_analyze counter only + * if we analyzed all columns; otherwise, there is still work for + * auto-analyze to do. */ if (!inh) - pgstat_report_analyze(onerel, totalrows, totaldeadrows); + pgstat_report_analyze(onerel, totalrows, totaldeadrows, + (va_cols == NIL)); /* If this isn't part of VACUUM ANALYZE, let index AMs do cleanup */ if (!(options & VACOPT_VACUUM)) diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c index 0b0b0446b9..3c862feb92 100644 --- a/src/backend/postmaster/pgstat.c +++ b/src/backend/postmaster/pgstat.c @@ -1346,11 +1346,15 @@ pgstat_report_vacuum(Oid tableoid, bool shared, * pgstat_report_analyze() - * * Tell the collector about the table we just analyzed. + * + * Caller must provide new live- and dead-tuples estimates, as well as a + * flag indicating whether to reset the changes_since_analyze counter. * -------- */ void pgstat_report_analyze(Relation rel, - PgStat_Counter livetuples, PgStat_Counter deadtuples) + PgStat_Counter livetuples, PgStat_Counter deadtuples, + bool resetcounter) { PgStat_MsgAnalyze msg; @@ -1387,6 +1391,7 @@ pgstat_report_analyze(Relation rel, msg.m_databaseid = rel->rd_rel->relisshared ? InvalidOid : MyDatabaseId; msg.m_tableoid = RelationGetRelid(rel); msg.m_autovacuum = IsAutoVacuumWorkerProcess(); + msg.m_resetcounter = resetcounter; msg.m_analyzetime = GetCurrentTimestamp(); msg.m_live_tuples = livetuples; msg.m_dead_tuples = deadtuples; @@ -5110,10 +5115,12 @@ pgstat_recv_analyze(PgStat_MsgAnalyze *msg, int len) tabentry->n_dead_tuples = msg->m_dead_tuples; /* - * We reset changes_since_analyze to zero, forgetting any changes that - * occurred while the ANALYZE was in progress. + * If commanded, reset changes_since_analyze to zero. This forgets any + * changes that were committed while the ANALYZE was in progress, but we + * have no good way to estimate how many of those there were. */ - tabentry->changes_since_analyze = 0; + if (msg->m_resetcounter) + tabentry->changes_since_analyze = 0; if (msg->m_autovacuum) { diff --git a/src/include/pgstat.h b/src/include/pgstat.h index 5738336c2a..fed4d2413c 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -382,6 +382,7 @@ typedef struct PgStat_MsgAnalyze Oid m_databaseid; Oid m_tableoid; bool m_autovacuum; + bool m_resetcounter; TimestampTz m_analyzetime; PgStat_Counter m_live_tuples; PgStat_Counter m_dead_tuples; @@ -932,7 +933,8 @@ extern void pgstat_report_autovac(Oid dboid); extern void pgstat_report_vacuum(Oid tableoid, bool shared, PgStat_Counter livetuples, PgStat_Counter deadtuples); extern void pgstat_report_analyze(Relation rel, - PgStat_Counter livetuples, PgStat_Counter deadtuples); + PgStat_Counter livetuples, PgStat_Counter deadtuples, + bool resetcounter); extern void pgstat_report_recovery_conflict(int reason); extern void pgstat_report_deadlock(void);