On 09.07.2020 22:16, Grigory Smolkin wrote:
On 7/8/20 11:41 PM, Konstantin Knizhnik wrote:
So looks like NUM_LOCK_PARTITIONS and MAXNUMMESSAGES constants have
to be replaced with GUCs.
To avoid division, we can specify log2 of this values, so shift can
be used instead.
And MAX_SIMUL_LWLOCKS should be defined as NUM_LOCK_PARTITIONS +
NUM_INDIVIDUAL_LWLOCKS + NAMED_LWLOCK_RESERVE.
Because I was involved in this particular case and don`t want it to
became a habit, I`m volunteering to test whatever patch this
discussion will produce.
You are welcome:)
diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c
index 68effcaed6..27f6328dca 100644
--- a/src/backend/access/heap/vacuumlazy.c
+++ b/src/backend/access/heap/vacuumlazy.c
@@ -607,7 +607,8 @@ heap_vacuum_rel(Relation onerel, VacuumParams *params,
pgstat_report_vacuum(RelationGetRelid(onerel),
onerel->rd_rel->relisshared,
new_live_tuples,
- vacrelstats->new_dead_tuples);
+ vacrelstats->new_dead_tuples,
+ OldestXmin);
pgstat_progress_end_command();
/* and log the action if appropriate */
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 9c7d4b0c60..0eed10fd65 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -92,6 +92,7 @@
#include "storage/lmgr.h"
#include "storage/pmsignal.h"
#include "storage/proc.h"
+#include "storage/procarray.h"
#include "storage/procsignal.h"
#include "storage/sinvaladt.h"
#include "storage/smgr.h"
@@ -2992,6 +2993,9 @@ relation_needs_vacanalyze(Oid relid,
TransactionId xidForceLimit;
MultiXactId multiForceLimit;
+ TransactionId oldestXmin;
+ Relation rel;
+
AssertArg(classForm != NULL);
AssertArg(OidIsValid(relid));
@@ -3076,6 +3080,10 @@ relation_needs_vacanalyze(Oid relid,
instuples = tabentry->inserts_since_vacuum;
anltuples = tabentry->changes_since_analyze;
+ rel = RelationIdGetRelation(relid);
+ oldestXmin = TransactionIdLimitedForOldSnapshots(GetOldestXmin(rel, PROCARRAY_FLAGS_VACUUM), rel);
+ RelationClose(rel);
+
vacthresh = (float4) vac_base_thresh + vac_scale_factor * reltuples;
vacinsthresh = (float4) vac_ins_base_thresh + vac_ins_scale_factor * reltuples;
anlthresh = (float4) anl_base_thresh + anl_scale_factor * reltuples;
@@ -3095,9 +3103,20 @@ relation_needs_vacanalyze(Oid relid,
vactuples, vacthresh, anltuples, anlthresh);
/* Determine if this table needs vacuum or analyze. */
- *dovacuum = force_vacuum || (vactuples > vacthresh) ||
- (vac_ins_base_thresh >= 0 && instuples > vacinsthresh);
- *doanalyze = (anltuples > anlthresh);
+ if (tabentry->autovac_oldest_xmin != oldestXmin)
+ {
+ *dovacuum = force_vacuum || (vactuples > vacthresh) ||
+ (vac_ins_base_thresh >= 0 && instuples > vacinsthresh);
+ *doanalyze = (anltuples > anlthresh);
+ elog(DEBUG1, "Consider relation %d tabentry=%p, tabentry->autovac_oldest_xmin=%d, oldestXmin=%d, dovacuum=%d, doanalyze=%d",
+ relid, tabentry, tabentry->autovac_oldest_xmin, oldestXmin, *dovacuum, *doanalyze);
+ }
+ else
+ {
+ elog(DEBUG1, "Skip autovacuum of relation %d", relid);
+ *dovacuum = force_vacuum;
+ *doanalyze = false;
+ }
}
else
{
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index c022597bc0..99db7884de 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -1461,7 +1461,8 @@ pgstat_report_autovac(Oid dboid)
*/
void
pgstat_report_vacuum(Oid tableoid, bool shared,
- PgStat_Counter livetuples, PgStat_Counter deadtuples)
+ PgStat_Counter livetuples, PgStat_Counter deadtuples,
+ TransactionId oldestXmin)
{
PgStat_MsgVacuum msg;
@@ -1475,6 +1476,7 @@ pgstat_report_vacuum(Oid tableoid, bool shared,
msg.m_vacuumtime = GetCurrentTimestamp();
msg.m_live_tuples = livetuples;
msg.m_dead_tuples = deadtuples;
+ msg.m_oldest_xmin = oldestXmin;
pgstat_send(&msg, sizeof(msg));
}
@@ -4838,6 +4840,7 @@ pgstat_get_tab_entry(PgStat_StatDBEntry *dbentry, Oid tableoid, bool create)
result->analyze_count = 0;
result->autovac_analyze_timestamp = 0;
result->autovac_analyze_count = 0;
+ result->autovac_oldest_xmin = InvalidTransactionId;
}
return result;
@@ -6007,6 +6010,7 @@ pgstat_recv_tabstat(PgStat_MsgTabstat *msg, int len)
tabentry->analyze_count = 0;
tabentry->autovac_analyze_timestamp = 0;
tabentry->autovac_analyze_count = 0;
+ tabentry->autovac_oldest_xmin = InvalidTransactionId;
}
else
{
@@ -6288,6 +6292,8 @@ pgstat_recv_vacuum(PgStat_MsgVacuum *msg, int len)
tabentry->n_live_tuples = msg->m_live_tuples;
tabentry->n_dead_tuples = msg->m_dead_tuples;
+ tabentry->autovac_oldest_xmin = msg->m_oldest_xmin;
+
/*
* It is quite possible that a non-aggressive VACUUM ended up skipping
* various pages, however, we'll zero the insert counter here regardless.
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 1387201382..ef92c5632f 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -383,6 +383,7 @@ typedef struct PgStat_MsgVacuum
TimestampTz m_vacuumtime;
PgStat_Counter m_live_tuples;
PgStat_Counter m_dead_tuples;
+ TransactionId m_oldest_xmin;
} PgStat_MsgVacuum;
@@ -692,6 +693,8 @@ typedef struct PgStat_StatTabEntry
PgStat_Counter analyze_count;
TimestampTz autovac_analyze_timestamp; /* autovacuum initiated */
PgStat_Counter autovac_analyze_count;
+
+ TransactionId autovac_oldest_xmin;
} PgStat_StatTabEntry;
@@ -1301,7 +1304,8 @@ extern void pgstat_reset_slru_counter(const char *);
extern void pgstat_report_autovac(Oid dboid);
extern void pgstat_report_vacuum(Oid tableoid, bool shared,
- PgStat_Counter livetuples, PgStat_Counter deadtuples);
+ PgStat_Counter livetuples, PgStat_Counter deadtuples,
+ TransactionId oldestXmin);
extern void pgstat_report_analyze(Relation rel,
PgStat_Counter livetuples, PgStat_Counter deadtuples,
bool resetcounter);
