Hi,
On Thu, Feb 19, 2026 at 01:27:10PM -0500, Andres Freund wrote:
> Hi,
>
> On 2026-02-19 13:06:52 +0900, Michael Paquier wrote:
> > On Tue, Feb 17, 2026 at 04:33:54PM +0000, Bertrand Drouvot wrote:
> > > Okay, done that way in the attached. To avoid overhead due to timing as
> > > much as
> > > possible, the patch simply relies on log_lock_waits and deadlock_timeout.
> > > It means
> > > that it relies on the existing code, and increments waits and wait_time
> > > only if
> > > log_lock_waits is on and if the session waited longer than
> > > deadlock_timeout.
> > >
> > > I did not want to dissociate the waits and wait_time increments so that
> > > their
> > > ratio could still make sense.
> > >
> > > That sounds like a good compromise, thoughts?
> >
> > else if (myWaitStatus == PROC_WAIT_STATUS_OK)
> > + {
> > + /* Increment the lock statistics counters */
> > + pgstat_count_lock_waits(locallock->tag.lock.locktag_type);
> > +
> > pgstat_count_lock_wait_time(locallock->tag.lock.locktag_type, msecs);
>
> Why do two external function calls? The function calls are at least as
> expensive as the work inside them, so doing this separately adds a fair bit of
> overhead.
Yeah, I also realized that and that was changed in v6 (you were looking at v5
to make this comment).
> > Not sure that it makes much sense to me to rely on log_lock_waits
> > being enabled to decide if this count and this time are aggregated.
> > The log information and the stats gathering are two separate things.
> > Wouldn't it make more sense to call pgstat_count_lock_waits() outside
> > of this code path, when we know myWaitStatus?
>
> IDK, it doesn't seem unreasonable to not duplicate work.
I don't think that the new GUC is introducing duplicate work (see 0003
attached),
that said it's introducing extra complexity in ProcSleep().
> If the delay is very
> short it's probably also not that interesting to track, but I guess that's
> debatable.
v6 was introducing timed_waits so that we have:
waits
timed_waits
wait_time
fastpath_exceeded
timed_waits and wait_time were incremented together and waits was incremented
unconditionally. I like the idea of being able to track the numbers of waits
whatever the value of log_lock_waits (or the new track_lock_timing) is. Also
one could compare waits vs timed_waits.
It's still done that way in the attached.
> I don't think it's worth having a separate GUC to track this. The realistic
> number of calls in a certain timespan to this is way way lower than something
> like track_io_timing, track_wal_io_timing or such. So I don't think we need an
> opt-out here like for those. If we eventually can reduce the overhead of the
> other track_* GUCs, we should remove them too, but I think that's further out.
Yeah, OTOH having a dedicated GUC for a clear separation of duties also makes
sense.
I don't have a strong opinion on it, but in the attached 0003 is adding
the new GUC. So that we can see what having a new GUC implies in ProcSleep() and
we can just get rid of 0003 if we think the GUC is not worth the extra
complexity.
Regards,
--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com
>From 1e506de67d19bcc98ad41bc2681aed07aaa5d9e8 Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <[email protected]>
Date: Tue, 29 Jul 2025 08:36:35 +0000
Subject: [PATCH v7 1/3] Add lock statistics
Adding a new stat kind PGSTAT_KIND_LOCK for the lock statistics.
This new statistic kind is a fixed one because its key is the lock type
so that we know its size is LOCKTAG_LAST_TYPE + 1.
This statistic kind records the following counters:
waits
timed_waits
wait_time
fastpath_exceeded
The timed_waits and wait_time counters are incremented if log_lock_waits is on
and the session waited longer than deadlock_timeout to acquire the lock.
waits is incremented unconditionally.
fastpath_exceeded is incremented when the lock can not be acquired via fast path
because the fast path slot limit was exceeded.
No extra details is added (like the ones, i.e relation oid, database oid, we
can find in pg_locks). The idea is to provide an idea on what the locking
behaviour looks like.
XXX: Bump stat file format
---
src/backend/storage/lmgr/lock.c | 58 ++++----
src/backend/storage/lmgr/proc.c | 9 ++
src/backend/utils/activity/Makefile | 1 +
src/backend/utils/activity/meson.build | 1 +
src/backend/utils/activity/pgstat.c | 18 +++
src/backend/utils/activity/pgstat_lock.c | 164 +++++++++++++++++++++++
src/include/pgstat.h | 29 ++++
src/include/utils/pgstat_internal.h | 21 +++
src/include/utils/pgstat_kind.h | 5 +-
src/tools/pgindent/typedefs.list | 4 +
10 files changed, 282 insertions(+), 28 deletions(-)
29.3% src/backend/storage/lmgr/
54.2% src/backend/utils/activity/
7.2% src/include/utils/
8.4% src/include/
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index e1168ad3837..8a0d970b26b 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -39,6 +39,7 @@
#include "access/xlogutils.h"
#include "miscadmin.h"
#include "pg_trace.h"
+#include "pgstat.h"
#include "storage/lmgr.h"
#include "storage/proc.h"
#include "storage/procarray.h"
@@ -984,37 +985,42 @@ LockAcquireExtended(const LOCKTAG *locktag,
* lock type on a relation we have already locked using the fast-path, but
* for now we don't worry about that case either.
*/
- if (EligibleForRelationFastPath(locktag, lockmode) &&
- FastPathLocalUseCounts[FAST_PATH_REL_GROUP(locktag->locktag_field2)] < FP_LOCK_SLOTS_PER_GROUP)
+ if (EligibleForRelationFastPath(locktag, lockmode))
{
- uint32 fasthashcode = FastPathStrongLockHashPartition(hashcode);
- bool acquired;
-
- /*
- * LWLockAcquire acts as a memory sequencing point, so it's safe to
- * assume that any strong locker whose increment to
- * FastPathStrongRelationLocks->counts becomes visible after we test
- * it has yet to begin to transfer fast-path locks.
- */
- LWLockAcquire(&MyProc->fpInfoLock, LW_EXCLUSIVE);
- if (FastPathStrongRelationLocks->count[fasthashcode] != 0)
- acquired = false;
- else
- acquired = FastPathGrantRelationLock(locktag->locktag_field2,
- lockmode);
- LWLockRelease(&MyProc->fpInfoLock);
- if (acquired)
+ if (FastPathLocalUseCounts[FAST_PATH_REL_GROUP(locktag->locktag_field2)] <
+ FP_LOCK_SLOTS_PER_GROUP)
{
+ uint32 fasthashcode = FastPathStrongLockHashPartition(hashcode);
+ bool acquired;
+
/*
- * The locallock might contain stale pointers to some old shared
- * objects; we MUST reset these to null before considering the
- * lock to be acquired via fast-path.
+ * LWLockAcquire acts as a memory sequencing point, so it's safe
+ * to assume that any strong locker whose increment to
+ * FastPathStrongRelationLocks->counts becomes visible after we
+ * test it has yet to begin to transfer fast-path locks.
*/
- locallock->lock = NULL;
- locallock->proclock = NULL;
- GrantLockLocal(locallock, owner);
- return LOCKACQUIRE_OK;
+ LWLockAcquire(&MyProc->fpInfoLock, LW_EXCLUSIVE);
+ if (FastPathStrongRelationLocks->count[fasthashcode] != 0)
+ acquired = false;
+ else
+ acquired = FastPathGrantRelationLock(locktag->locktag_field2,
+ lockmode);
+ LWLockRelease(&MyProc->fpInfoLock);
+ if (acquired)
+ {
+ /*
+ * The locallock might contain stale pointers to some old
+ * shared objects; we MUST reset these to null before
+ * considering the lock to be acquired via fast-path.
+ */
+ locallock->lock = NULL;
+ locallock->proclock = NULL;
+ GrantLockLocal(locallock, owner);
+ return LOCKACQUIRE_OK;
+ }
}
+ else
+ pgstat_count_lock_fastpath_exceeded(locallock->tag.lock.locktag_type);
}
/*
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index fd8318bdf3d..bee4a3c2b89 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -1609,9 +1609,15 @@ ProcSleep(LOCALLOCK *locallock)
"Processes holding the lock: %s. Wait queue: %s.",
lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
else if (myWaitStatus == PROC_WAIT_STATUS_OK)
+ {
+ /* Increment the timed lock statistics counters */
+ pgstat_count_lock_timed_wait(locallock->tag.lock.locktag_type,
+ msecs);
+
ereport(LOG,
(errmsg("process %d acquired %s on %s after %ld.%03d ms",
MyProcPid, modename, buf.data, msecs, usecs)));
+ }
else
{
Assert(myWaitStatus == PROC_WAIT_STATUS_ERROR);
@@ -1646,6 +1652,9 @@ ProcSleep(LOCALLOCK *locallock)
}
} while (myWaitStatus == PROC_WAIT_STATUS_WAITING);
+ /* Count lock waits unconditionally, regardless of log_lock_waits */
+ pgstat_count_lock_waits(locallock->tag.lock.locktag_type);
+
/*
* Disable the timers, if they are still running. As in LockErrorCleanup,
* we must preserve the LOCK_TIMEOUT indicator flag: if a lock timeout has
diff --git a/src/backend/utils/activity/Makefile b/src/backend/utils/activity/Makefile
index c37bfb350bb..ca3ef89bf59 100644
--- a/src/backend/utils/activity/Makefile
+++ b/src/backend/utils/activity/Makefile
@@ -26,6 +26,7 @@ OBJS = \
pgstat_database.o \
pgstat_function.o \
pgstat_io.o \
+ pgstat_lock.o \
pgstat_relation.o \
pgstat_replslot.o \
pgstat_shmem.o \
diff --git a/src/backend/utils/activity/meson.build b/src/backend/utils/activity/meson.build
index 53bd5a246ca..1aa7ece5290 100644
--- a/src/backend/utils/activity/meson.build
+++ b/src/backend/utils/activity/meson.build
@@ -11,6 +11,7 @@ backend_sources += files(
'pgstat_database.c',
'pgstat_function.c',
'pgstat_io.c',
+ 'pgstat_lock.c',
'pgstat_relation.c',
'pgstat_replslot.c',
'pgstat_shmem.c',
diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c
index 11bb71cad5a..eb8ccbaa628 100644
--- a/src/backend/utils/activity/pgstat.c
+++ b/src/backend/utils/activity/pgstat.c
@@ -83,6 +83,7 @@
* - pgstat_database.c
* - pgstat_function.c
* - pgstat_io.c
+ * - pgstat_lock.c
* - pgstat_relation.c
* - pgstat_replslot.c
* - pgstat_slru.c
@@ -448,6 +449,23 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.snapshot_cb = pgstat_io_snapshot_cb,
},
+ [PGSTAT_KIND_LOCK] = {
+ .name = "lock",
+
+ .fixed_amount = true,
+ .write_to_file = true,
+
+ .snapshot_ctl_off = offsetof(PgStat_Snapshot, lock),
+ .shared_ctl_off = offsetof(PgStat_ShmemControl, lock),
+ .shared_data_off = offsetof(PgStatShared_Lock, stats),
+ .shared_data_len = sizeof(((PgStatShared_Lock *) 0)->stats),
+
+ .flush_static_cb = pgstat_lock_flush_cb,
+ .init_shmem_cb = pgstat_lock_init_shmem_cb,
+ .reset_all_cb = pgstat_lock_reset_all_cb,
+ .snapshot_cb = pgstat_lock_snapshot_cb,
+ },
+
[PGSTAT_KIND_SLRU] = {
.name = "slru",
diff --git a/src/backend/utils/activity/pgstat_lock.c b/src/backend/utils/activity/pgstat_lock.c
new file mode 100644
index 00000000000..b410f376d49
--- /dev/null
+++ b/src/backend/utils/activity/pgstat_lock.c
@@ -0,0 +1,164 @@
+/* -------------------------------------------------------------------------
+ *
+ * pgstat_lock.c
+ * Implementation of lock statistics.
+ *
+ * This file contains the implementation of lock statistics. It is kept separate
+ * from pgstat.c to enforce the line between the statistics access / storage
+ * implementation and the details about individual types of statistics.
+ *
+ * Copyright (c) 2021-2025, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/backend/utils/activity/pgstat_lock.c
+ * -------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "utils/pgstat_internal.h"
+
+static PgStat_PendingLock PendingLockStats;
+static bool have_lockstats = false;
+
+/*
+ * Simpler wrapper of pgstat_lock_flush_cb()
+ */
+void
+pgstat_lock_flush(bool nowait)
+{
+ (void) pgstat_lock_flush_cb(nowait);
+}
+
+/*
+ * Flush out locally pending lock statistics
+ *
+ * If no stats have been recorded, this function returns false.
+ *
+ * If nowait is true, this function returns true if the lock could not be
+ * acquired. Otherwise, return false.
+ */
+bool
+pgstat_lock_flush_cb(bool nowait)
+{
+ LWLock *lcktype_lock;
+ PgStat_LockEntry *lck_shstats;
+ bool lock_not_acquired = false;
+
+ if (!have_lockstats)
+ return false;
+
+ for (int i = 0; i <= LOCKTAG_LAST_TYPE; i++)
+ {
+ lcktype_lock = &pgStatLocal.shmem->lock.locks[i];
+ lck_shstats =
+ &pgStatLocal.shmem->lock.stats.stats[i];
+
+ if (!nowait)
+ LWLockAcquire(lcktype_lock, LW_EXCLUSIVE);
+ else if (!LWLockConditionalAcquire(lcktype_lock, LW_EXCLUSIVE))
+ {
+ lock_not_acquired = true;
+ continue;
+ }
+
+#define LOCKSTAT_ACC(fld) \
+ (lck_shstats->fld += PendingLockStats.stats[i].fld)
+ LOCKSTAT_ACC(waits);
+ LOCKSTAT_ACC(timed_waits);
+ LOCKSTAT_ACC(wait_time);
+ LOCKSTAT_ACC(fastpath_exceeded);
+#undef LOCKSTAT_ACC
+
+ LWLockRelease(lcktype_lock);
+ }
+
+ memset(&PendingLockStats, 0, sizeof(PendingLockStats));
+
+ have_lockstats = false;
+
+ return lock_not_acquired;
+}
+
+
+void
+pgstat_lock_init_shmem_cb(void *stats)
+{
+ PgStatShared_Lock *stat_shmem = (PgStatShared_Lock *) stats;
+
+ for (int i = 0; i <= LOCKTAG_LAST_TYPE; i++)
+ LWLockInitialize(&stat_shmem->locks[i], LWTRANCHE_PGSTATS_DATA);
+}
+
+void
+pgstat_lock_reset_all_cb(TimestampTz ts)
+{
+ for (int i = 0; i <= LOCKTAG_LAST_TYPE; i++)
+ {
+ LWLock *lcktype_lock = &pgStatLocal.shmem->lock.locks[i];
+ PgStat_LockEntry *lck_shstats = &pgStatLocal.shmem->lock.stats.stats[i];
+
+ LWLockAcquire(lcktype_lock, LW_EXCLUSIVE);
+
+ /*
+ * Use the lock in the first lock type PgStat_LockEntry to protect the
+ * reset timestamp as well.
+ */
+ if (i == 0)
+ pgStatLocal.shmem->lock.stats.stat_reset_timestamp = ts;
+
+ memset(lck_shstats, 0, sizeof(*lck_shstats));
+ LWLockRelease(lcktype_lock);
+ }
+}
+
+void
+pgstat_lock_snapshot_cb(void)
+{
+ for (int i = 0; i <= LOCKTAG_LAST_TYPE; i++)
+ {
+ LWLock *lcktype_lock = &pgStatLocal.shmem->lock.locks[i];
+ PgStat_LockEntry *lck_shstats = &pgStatLocal.shmem->lock.stats.stats[i];
+ PgStat_LockEntry *lck_snap = &pgStatLocal.snapshot.lock.stats[i];
+
+ LWLockAcquire(lcktype_lock, LW_SHARED);
+
+ /*
+ * Use the lock in the first lock type PgStat_LockEntry to protect the
+ * reset timestamp as well.
+ */
+ if (i == 0)
+ pgStatLocal.snapshot.lock.stat_reset_timestamp =
+ pgStatLocal.shmem->lock.stats.stat_reset_timestamp;
+
+ /* using struct assignment due to better type safety */
+ *lck_snap = *lck_shstats;
+ LWLockRelease(lcktype_lock);
+ }
+}
+
+#define PGSTAT_COUNT_LOCK_FUNC(stat) \
+void \
+CppConcat(pgstat_count_lock_,stat)(uint8 locktag_type) \
+{ \
+ Assert(locktag_type <= LOCKTAG_LAST_TYPE); \
+ PendingLockStats.stats[locktag_type].stat++; \
+ have_lockstats = true; \
+ pgstat_report_fixed = true; \
+}
+
+/* pgstat_count_lock_waits */
+PGSTAT_COUNT_LOCK_FUNC(waits)
+
+/* pgstat_count_lock_fastpath_exceeded */
+PGSTAT_COUNT_LOCK_FUNC(fastpath_exceeded)
+
+void
+pgstat_count_lock_timed_wait(uint8 locktag_type, long msecs)
+{
+ Assert(locktag_type <= LOCKTAG_LAST_TYPE);
+ PendingLockStats.stats[locktag_type].timed_waits++;
+ PendingLockStats.stats[locktag_type].wait_time += (PgStat_Counter) msecs;
+ have_lockstats = true;
+ pgstat_report_fixed = true;
+}
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 9bb777c3d5a..9c4508d5544 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -16,6 +16,7 @@
#include "portability/instr_time.h"
#include "postmaster/pgarch.h" /* for MAX_XFN_CHARS */
#include "replication/conflict.h"
+#include "storage/lock.h"
#include "utils/backend_progress.h" /* for backward compatibility */ /* IWYU pragma: export */
#include "utils/backend_status.h" /* for backward compatibility */ /* IWYU pragma: export */
#include "utils/pgstat_kind.h"
@@ -341,6 +342,25 @@ typedef struct PgStat_IO
PgStat_BktypeIO stats[BACKEND_NUM_TYPES];
} PgStat_IO;
+typedef struct PgStat_LockEntry
+{
+ PgStat_Counter waits;
+ PgStat_Counter timed_waits;
+ PgStat_Counter wait_time; /* time in milliseconds */
+ PgStat_Counter fastpath_exceeded;
+} PgStat_LockEntry;
+
+typedef struct PgStat_PendingLock
+{
+ PgStat_LockEntry stats[LOCKTAG_LAST_TYPE + 1];
+} PgStat_PendingLock;
+
+typedef struct PgStat_Lock
+{
+ TimestampTz stat_reset_timestamp;
+ PgStat_LockEntry stats[LOCKTAG_LAST_TYPE + 1];
+} PgStat_Lock;
+
typedef struct PgStat_StatDBEntry
{
PgStat_Counter xact_commit;
@@ -613,6 +633,15 @@ extern bool pgstat_tracks_io_op(BackendType bktype, IOObject io_object,
IOContext io_context, IOOp io_op);
+/*
+ * Functions in pgstat_lock.c
+ */
+
+extern void pgstat_lock_flush(bool nowait);
+extern void pgstat_count_lock_waits(uint8 locktag_type);
+extern void pgstat_count_lock_fastpath_exceeded(uint8 locktag_type);
+extern void pgstat_count_lock_timed_wait(uint8 locktag_type, long msecs);
+
/*
* Functions in pgstat_database.c
*/
diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h
index 9b8fbae00ed..97704421a92 100644
--- a/src/include/utils/pgstat_internal.h
+++ b/src/include/utils/pgstat_internal.h
@@ -464,6 +464,16 @@ typedef struct PgStatShared_IO
PgStat_IO stats;
} PgStatShared_IO;
+typedef struct PgStatShared_Lock
+{
+ /*
+ * locks[i] protects stats.stats[i]. locks[0] also protects
+ * stats.stat_reset_timestamp.
+ */
+ LWLock locks[LOCKTAG_LAST_TYPE + 1];
+ PgStat_Lock stats;
+} PgStatShared_Lock;
+
typedef struct PgStatShared_SLRU
{
/* lock protects ->stats */
@@ -570,6 +580,7 @@ typedef struct PgStat_ShmemControl
PgStatShared_BgWriter bgwriter;
PgStatShared_Checkpointer checkpointer;
PgStatShared_IO io;
+ PgStatShared_Lock lock;
PgStatShared_SLRU slru;
PgStatShared_Wal wal;
@@ -602,6 +613,8 @@ typedef struct PgStat_Snapshot
PgStat_IO io;
+ PgStat_Lock lock;
+
PgStat_SLRUStats slru[SLRU_NUM_ELEMENTS];
PgStat_WalStats wal;
@@ -752,6 +765,14 @@ extern void pgstat_io_init_shmem_cb(void *stats);
extern void pgstat_io_reset_all_cb(TimestampTz ts);
extern void pgstat_io_snapshot_cb(void);
+/*
+ * Functions in pgstat_lock.c
+ */
+
+extern bool pgstat_lock_flush_cb(bool nowait);
+extern void pgstat_lock_init_shmem_cb(void *stats);
+extern void pgstat_lock_reset_all_cb(TimestampTz ts);
+extern void pgstat_lock_snapshot_cb(void);
/*
* Functions in pgstat_relation.c
diff --git a/src/include/utils/pgstat_kind.h b/src/include/utils/pgstat_kind.h
index c30b6235623..2d78a029683 100644
--- a/src/include/utils/pgstat_kind.h
+++ b/src/include/utils/pgstat_kind.h
@@ -36,8 +36,9 @@
#define PGSTAT_KIND_BGWRITER 8
#define PGSTAT_KIND_CHECKPOINTER 9
#define PGSTAT_KIND_IO 10
-#define PGSTAT_KIND_SLRU 11
-#define PGSTAT_KIND_WAL 12
+#define PGSTAT_KIND_LOCK 11
+#define PGSTAT_KIND_SLRU 12
+#define PGSTAT_KIND_WAL 13
#define PGSTAT_KIND_BUILTIN_MIN PGSTAT_KIND_DATABASE
#define PGSTAT_KIND_BUILTIN_MAX PGSTAT_KIND_WAL
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 241945734ec..0432862061b 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2255,6 +2255,7 @@ PgStatShared_Database
PgStatShared_Function
PgStatShared_HashEntry
PgStatShared_IO
+PgStatShared_Lock
PgStatShared_Relation
PgStatShared_ReplSlot
PgStatShared_SLRU
@@ -2277,8 +2278,11 @@ PgStat_HashKey
PgStat_IO
PgStat_KindInfo
PgStat_LocalState
+PgStat_Lock
+PgStat_LockEntry
PgStat_PendingDroppedStatsItem
PgStat_PendingIO
+PgStat_PendingLock
PgStat_SLRUStats
PgStat_ShmemControl
PgStat_Snapshot
--
2.34.1
>From 9ed0b32bdf025f2abeb4848d70c76de184e0a214 Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <[email protected]>
Date: Thu, 31 Jul 2025 09:35:31 +0000
Subject: [PATCH v7 2/3] Add the pg_stat_lock view
This new view reports lock statistics.
Note that it does not omit combinations which do not make sense (as pg_locks
does).
Also wait_time is reported as bigint as the deadlock_timeout default value is
1s.
This commit also adds documentation and a few tests.
XXX: Bump catversion
---
doc/src/sgml/monitoring.sgml | 125 +++++++++++++++
src/backend/catalog/system_views.sql | 10 ++
src/backend/utils/activity/pgstat_lock.c | 8 +
src/backend/utils/adt/pgstatfuncs.c | 40 +++++
src/include/catalog/pg_proc.dat | 9 ++
src/include/pgstat.h | 1 +
src/test/isolation/expected/stats.out | 189 +++++++++++++++++++++++
src/test/isolation/expected/stats_1.out | 189 +++++++++++++++++++++++
src/test/isolation/specs/stats.spec | 95 ++++++++++++
src/test/regress/expected/rules.out | 7 +
src/test/regress/expected/stats.out | 48 ++++++
src/test/regress/sql/stats.sql | 36 +++++
12 files changed, 757 insertions(+)
16.7% doc/src/sgml/
5.0% src/backend/utils/adt/
53.6% src/test/isolation/expected/
11.1% src/test/isolation/specs/
5.6% src/test/regress/expected/
3.9% src/test/regress/sql/
3.7% src/
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index b77d189a500..cfcb8189418 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -493,6 +493,15 @@ postgres 27093 0.0 0.0 30096 2752 ? Ss 11:34 0:00 postgres: ser
</entry>
</row>
+ <row>
+ <entry><structname>pg_stat_lock</structname><indexterm><primary>pg_stat_lock</primary></indexterm></entry>
+ <entry>
+ One row for each lock type, containing cluster-wide locks statistics.
+ See <link linkend="monitoring-pg-stat-lock-view">
+ <structname>pg_stat_lock</structname></link> for details.
+ </entry>
+ </row>
+
<row>
<entry><structname>pg_stat_replication_slots</structname><indexterm><primary>pg_stat_replication_slots</primary></indexterm></entry>
<entry>One row per replication slot, showing statistics about the
@@ -3124,6 +3133,116 @@ description | Waiting for a newly initialized WAL file to reach durable storage
</sect2>
+
+ <sect2 id="monitoring-pg-stat-lock-view">
+ <title><structname>pg_stat_lock</structname></title>
+
+ <indexterm>
+ <primary>pg_stat_lock</primary>
+ </indexterm>
+
+ <para>
+ The <structname>pg_stat_lock</structname> view will contain one row for each
+ lock type, showing cluster-wide locks statistics.
+ </para>
+
+ <table id="pg-stat-lock-view" xreflabel="pg_stat_lock">
+ <title><structname>pg_stat_lock</structname> View</title>
+ <tgroup cols="1">
+ <thead>
+ <row>
+ <entry role="catalog_table_entry">
+ <para role="column_definition">
+ Column Type
+ </para>
+ <para>
+ Description
+ </para>
+ </entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry role="catalog_table_entry">
+ <para role="column_definition">
+ <structfield>locktype</structfield> <type>text</type>
+ </para>
+ <para>
+ Type of the lockable object. See <link linkend="view-pg-locks">
+ <structname>pg_locks</structname></link> for details.
+ </para>
+ </entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry">
+ <para role="column_definition">
+ <structfield>waits</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Number of times a lock of this type had to wait because of a
+ conflicting lock.
+ </para>
+ </entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry">
+ <para role="column_definition">
+ <structfield>timed_waits</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Number of times a lock of this type had to wait because of a
+ conflicting lock. Only incremented when <xref linkend="guc-log-lock-waits"/>
+ is enabled and the lock was successfully acquired after waiting longer
+ than <xref linkend="guc-deadlock-timeout"/>.
+ </para>
+ </entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry">
+ <para role="column_definition">
+ <structfield>wait_time</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Total time spent waiting for locks of this type, in milliseconds.
+ Only incremented when <xref linkend="guc-log-lock-waits"/> is enabled and
+ the lock was successfully acquired after waiting longer than
+ <xref linkend="guc-deadlock-timeout"/>.
+ </para>
+ </entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry">
+ <para role="column_definition">
+ <structfield>fastpath_exceeded</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Number of times a lock of this type could not be acquired via fast path
+ because the fast path slot limit was exceeded. You may want to increase
+ <xref linkend="guc-max-locks-per-transaction"/> if you feel this counter
+ is too high.
+ </para>
+ </entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry">
+ <para role="column_definition">
+ <structfield>stats_reset</structfield> <type>timestamp with time zone</type>
+ </para>
+ <para>
+ Time at which these statistics were last reset.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </sect2>
+
<sect2 id="monitoring-pg-stat-bgwriter-view">
<title><structname>pg_stat_bgwriter</structname></title>
@@ -5195,6 +5314,12 @@ description | Waiting for a newly initialized WAL file to reach durable storage
<structname>pg_stat_io</structname> view.
</para>
</listitem>
+ <listitem>
+ <para>
+ <literal>lock</literal>: Reset all the counters shown in the
+ <structname>pg_stat_lock</structname> view.
+ </para>
+ </listitem>
<listitem>
<para>
<literal>recovery_prefetch</literal>: Reset all the counters shown in
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 1ea8f1faa9e..dcf12a202e0 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -985,6 +985,16 @@ CREATE VIEW pg_stat_slru AS
s.stats_reset
FROM pg_stat_get_slru() s;
+CREATE VIEW pg_stat_lock AS
+ SELECT
+ l.locktype,
+ l.waits,
+ l.timed_waits,
+ l.wait_time,
+ l.fastpath_exceeded,
+ l.stats_reset
+ FROM pg_stat_get_lock() l;
+
CREATE VIEW pg_stat_wal_receiver AS
SELECT
s.pid,
diff --git a/src/backend/utils/activity/pgstat_lock.c b/src/backend/utils/activity/pgstat_lock.c
index b410f376d49..451fba4f8d9 100644
--- a/src/backend/utils/activity/pgstat_lock.c
+++ b/src/backend/utils/activity/pgstat_lock.c
@@ -21,6 +21,14 @@
static PgStat_PendingLock PendingLockStats;
static bool have_lockstats = false;
+PgStat_Lock *
+pgstat_fetch_stat_lock(void)
+{
+ pgstat_snapshot_fixed(PGSTAT_KIND_LOCK);
+
+ return &pgStatLocal.snapshot.lock;
+}
+
/*
* Simpler wrapper of pgstat_lock_flush_cb()
*/
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index b1df96e7b0b..3b7cbdb82be 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -1737,6 +1737,43 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
wal_stats->stat_reset_timestamp));
}
+Datum
+pg_stat_get_lock(PG_FUNCTION_ARGS)
+{
+#define PG_STAT_LOCK_COLS 6
+ ReturnSetInfo *rsinfo;
+ PgStat_Lock *lock_stats;
+
+ InitMaterializedSRF(fcinfo, 0);
+ rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+
+ lock_stats = pgstat_fetch_stat_lock();
+
+ for (int lcktype = 0; lcktype <= LOCKTAG_LAST_TYPE; lcktype++)
+ {
+ const char *locktypename;
+ Datum values[PG_STAT_LOCK_COLS] = {0};
+ bool nulls[PG_STAT_LOCK_COLS] = {0};
+ PgStat_LockEntry *lck_stats = &lock_stats->stats[lcktype];
+ int i = 0;
+
+ locktypename = LockTagTypeNames[lcktype];
+
+ values[i++] = CStringGetTextDatum(locktypename);
+ values[i++] = Int64GetDatum(lck_stats->waits);
+ values[i++] = Int64GetDatum(lck_stats->timed_waits);
+ values[i++] = Int64GetDatum(lck_stats->wait_time);
+ values[i++] = Int64GetDatum(lck_stats->fastpath_exceeded);
+ values[i] = TimestampTzGetDatum(lock_stats->stat_reset_timestamp);
+
+ Assert(i + 1 == PG_STAT_LOCK_COLS);
+
+ tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+ }
+
+ return (Datum) 0;
+}
+
/*
* Returns statistics of SLRU caches.
*/
@@ -1921,6 +1958,7 @@ pg_stat_reset_shared(PG_FUNCTION_ARGS)
pgstat_reset_of_kind(PGSTAT_KIND_BGWRITER);
pgstat_reset_of_kind(PGSTAT_KIND_CHECKPOINTER);
pgstat_reset_of_kind(PGSTAT_KIND_IO);
+ pgstat_reset_of_kind(PGSTAT_KIND_LOCK);
XLogPrefetchResetStats();
pgstat_reset_of_kind(PGSTAT_KIND_SLRU);
pgstat_reset_of_kind(PGSTAT_KIND_WAL);
@@ -1938,6 +1976,8 @@ pg_stat_reset_shared(PG_FUNCTION_ARGS)
pgstat_reset_of_kind(PGSTAT_KIND_CHECKPOINTER);
else if (strcmp(target, "io") == 0)
pgstat_reset_of_kind(PGSTAT_KIND_IO);
+ else if (strcmp(target, "lock") == 0)
+ pgstat_reset_of_kind(PGSTAT_KIND_LOCK);
else if (strcmp(target, "recovery_prefetch") == 0)
XLogPrefetchResetStats();
else if (strcmp(target, "slru") == 0)
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index dac40992cbc..3cd497a8e1f 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -6027,6 +6027,15 @@
proargnames => '{backend_type,object,context,reads,read_bytes,read_time,writes,write_bytes,write_time,writebacks,writeback_time,extends,extend_bytes,extend_time,hits,evictions,reuses,fsyncs,fsync_time,stats_reset}',
prosrc => 'pg_stat_get_io' },
+{ oid => '9375', descr => 'statistics: per lock type statistics',
+ proname => 'pg_stat_get_lock', prorows => '10', proretset => 't',
+ provolatile => 'v', proparallel => 'r', prorettype => 'record',
+ proargtypes => '',
+ proallargtypes => '{text,int8,int8,int8,int8,timestamptz}',
+ proargmodes => '{o,o,o,o,o,o}',
+ proargnames => '{locktype,waits,timed_waits,wait_time,fastpath_exceeded,stats_reset}',
+ prosrc => 'pg_stat_get_lock' },
+
{ oid => '6386', descr => 'statistics: backend IO statistics',
proname => 'pg_stat_get_backend_io', prorows => '5', proretset => 't',
provolatile => 'v', proparallel => 'r', prorettype => 'record',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 9c4508d5544..a4cc006794d 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -641,6 +641,7 @@ extern void pgstat_lock_flush(bool nowait);
extern void pgstat_count_lock_waits(uint8 locktag_type);
extern void pgstat_count_lock_fastpath_exceeded(uint8 locktag_type);
extern void pgstat_count_lock_timed_wait(uint8 locktag_type, long msecs);
+extern PgStat_Lock *pgstat_fetch_stat_lock(void);
/*
* Functions in pgstat_database.c
diff --git a/src/test/isolation/expected/stats.out b/src/test/isolation/expected/stats.out
index cfad309ccf3..86d70a0705c 100644
--- a/src/test/isolation/expected/stats.out
+++ b/src/test/isolation/expected/stats.out
@@ -3751,3 +3751,192 @@ test_stat_func| 1|t |t
(1 row)
step s1_commit: COMMIT;
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s1_begin: BEGIN;
+step s1_lock_relation: LOCK TABLE test_stat_tab;
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_lock_relation: LOCK TABLE test_stat_tab; <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_commit: COMMIT;
+step s2_lock_relation: <... completed>
+step s2_commit: COMMIT;
+step s2_report_stat_lock_relation: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'relation';
+?column?|?column?|?column?
+--------+--------+--------
+t |t |t
+(1 row)
+
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_table_insert s1_begin s1_table_update_k1 s2_begin s2_ff s2_table_update_k1 s1_sleep s1_commit s2_commit s2_report_stat_lock_transactionid
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s1_table_insert: INSERT INTO test_stat_tab(key, value) VALUES('k1', 1), ('k2', 1), ('k3', 1);
+step s1_begin: BEGIN;
+step s1_table_update_k1: UPDATE test_stat_tab SET value = value + 1 WHERE key = 'k1';
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_table_update_k1: UPDATE test_stat_tab SET value = value + 1 WHERE key = 'k1'; <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_commit: COMMIT;
+step s2_table_update_k1: <... completed>
+step s2_commit: COMMIT;
+step s2_report_stat_lock_transactionid: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'transactionid';
+?column?|?column?|?column?
+--------+--------+--------
+t |t |t
+(1 row)
+
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_lock_advisory_lock s2_begin s2_ff s2_lock_advisory_lock s1_sleep s1_lock_advisory_unlock s2_lock_advisory_unlock s2_commit s2_report_stat_lock_advisory
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s1_lock_advisory_lock: SELECT pg_advisory_lock(1);
+pg_advisory_lock
+----------------
+
+(1 row)
+
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_lock_advisory_lock: SELECT pg_advisory_lock(1); <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_lock_advisory_unlock: SELECT pg_advisory_unlock(1);
+pg_advisory_unlock
+------------------
+t
+(1 row)
+
+step s2_lock_advisory_lock: <... completed>
+pg_advisory_lock
+----------------
+
+(1 row)
+
+step s2_lock_advisory_unlock: SELECT pg_advisory_unlock(1);
+pg_advisory_unlock
+------------------
+t
+(1 row)
+
+step s2_commit: COMMIT;
+step s2_report_stat_lock_advisory: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'advisory';
+?column?|?column?|?column?
+--------+--------+--------
+t |t |t
+(1 row)
+
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_unset_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_unset_log_lock_waits: SET log_lock_waits = off;
+step s1_begin: BEGIN;
+step s1_lock_relation: LOCK TABLE test_stat_tab;
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_lock_relation: LOCK TABLE test_stat_tab; <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_commit: COMMIT;
+step s2_lock_relation: <... completed>
+step s2_commit: COMMIT;
+step s2_report_stat_lock_relation: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'relation';
+?column?|?column?|?column?
+--------+--------+--------
+t |f |f
+(1 row)
+
diff --git a/src/test/isolation/expected/stats_1.out b/src/test/isolation/expected/stats_1.out
index e1d937784cb..4e4c68b4525 100644
--- a/src/test/isolation/expected/stats_1.out
+++ b/src/test/isolation/expected/stats_1.out
@@ -3775,3 +3775,192 @@ test_stat_func| 1|t |t
(1 row)
step s1_commit: COMMIT;
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s1_begin: BEGIN;
+step s1_lock_relation: LOCK TABLE test_stat_tab;
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_lock_relation: LOCK TABLE test_stat_tab; <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_commit: COMMIT;
+step s2_lock_relation: <... completed>
+step s2_commit: COMMIT;
+step s2_report_stat_lock_relation: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'relation';
+?column?|?column?|?column?
+--------+--------+--------
+t |t |t
+(1 row)
+
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_table_insert s1_begin s1_table_update_k1 s2_begin s2_ff s2_table_update_k1 s1_sleep s1_commit s2_commit s2_report_stat_lock_transactionid
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s1_table_insert: INSERT INTO test_stat_tab(key, value) VALUES('k1', 1), ('k2', 1), ('k3', 1);
+step s1_begin: BEGIN;
+step s1_table_update_k1: UPDATE test_stat_tab SET value = value + 1 WHERE key = 'k1';
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_table_update_k1: UPDATE test_stat_tab SET value = value + 1 WHERE key = 'k1'; <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_commit: COMMIT;
+step s2_table_update_k1: <... completed>
+step s2_commit: COMMIT;
+step s2_report_stat_lock_transactionid: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'transactionid';
+?column?|?column?|?column?
+--------+--------+--------
+t |t |t
+(1 row)
+
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_lock_advisory_lock s2_begin s2_ff s2_lock_advisory_lock s1_sleep s1_lock_advisory_unlock s2_lock_advisory_unlock s2_commit s2_report_stat_lock_advisory
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s1_lock_advisory_lock: SELECT pg_advisory_lock(1);
+pg_advisory_lock
+----------------
+
+(1 row)
+
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_lock_advisory_lock: SELECT pg_advisory_lock(1); <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_lock_advisory_unlock: SELECT pg_advisory_unlock(1);
+pg_advisory_unlock
+------------------
+t
+(1 row)
+
+step s2_lock_advisory_lock: <... completed>
+pg_advisory_lock
+----------------
+
+(1 row)
+
+step s2_lock_advisory_unlock: SELECT pg_advisory_unlock(1);
+pg_advisory_unlock
+------------------
+t
+(1 row)
+
+step s2_commit: COMMIT;
+step s2_report_stat_lock_advisory: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'advisory';
+?column?|?column?|?column?
+--------+--------+--------
+t |t |t
+(1 row)
+
+
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_unset_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s1_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s1_reset_stat_lock: SELECT pg_stat_reset_shared('lock');
+pg_stat_reset_shared
+--------------------
+
+(1 row)
+
+step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
+step s2_unset_log_lock_waits: SET log_lock_waits = off;
+step s1_begin: BEGIN;
+step s1_lock_relation: LOCK TABLE test_stat_tab;
+step s2_begin: BEGIN;
+step s2_ff: SELECT pg_stat_force_next_flush();
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_lock_relation: LOCK TABLE test_stat_tab; <waiting ...>
+step s1_sleep: SELECT pg_sleep(0.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_commit: COMMIT;
+step s2_lock_relation: <... completed>
+step s2_commit: COMMIT;
+step s2_report_stat_lock_relation: SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'relation';
+?column?|?column?|?column?
+--------+--------+--------
+t |f |f
+(1 row)
+
diff --git a/src/test/isolation/specs/stats.spec b/src/test/isolation/specs/stats.spec
index da16710da0f..d4b53545198 100644
--- a/src/test/isolation/specs/stats.spec
+++ b/src/test/isolation/specs/stats.spec
@@ -130,6 +130,14 @@ step s1_slru_check_stats {
WHERE before.stat = 'blks_zeroed';
}
+# Lock stats steps
+step s1_set_deadlock_timeout { SET deadlock_timeout = '10ms'; }
+step s1_set_log_lock_waits { SET log_lock_waits = on; }
+step s1_reset_stat_lock { SELECT pg_stat_reset_shared('lock'); }
+step s1_sleep { SELECT pg_sleep(0.5); }
+step s1_lock_relation { LOCK TABLE test_stat_tab; }
+step s1_lock_advisory_lock { SELECT pg_advisory_lock(1); }
+step s1_lock_advisory_unlock { SELECT pg_advisory_unlock(1); }
session s2
setup { SET stats_fetch_consistency = 'none'; }
@@ -164,6 +172,16 @@ step s2_big_notify { SELECT pg_notify('stats_test_use',
repeat(i::text, current_setting('block_size')::int / 2)) FROM generate_series(1, 3) g(i);
}
+# Lock stats steps
+step s2_set_deadlock_timeout { SET deadlock_timeout = '10ms'; }
+step s2_set_log_lock_waits { SET log_lock_waits = on; }
+step s2_unset_log_lock_waits { SET log_lock_waits = off; }
+step s2_report_stat_lock_relation { SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'relation'; }
+step s2_report_stat_lock_transactionid { SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'transactionid'; }
+step s2_report_stat_lock_advisory { SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'advisory'; }
+step s2_lock_relation { LOCK TABLE test_stat_tab; }
+step s2_lock_advisory_lock { SELECT pg_advisory_lock(1); }
+step s2_lock_advisory_unlock { SELECT pg_advisory_unlock(1); }
######################
# Function stats tests
@@ -765,3 +783,80 @@ permutation
s1_clear_snapshot
s1_func_stats
s1_commit
+
+######################
+# Lock stats tests
+######################
+
+# relation lock
+
+permutation
+ s1_set_deadlock_timeout
+ s1_reset_stat_lock
+ s1_set_log_lock_waits
+ s2_set_deadlock_timeout
+ s2_set_log_lock_waits
+ s1_begin
+ s1_lock_relation
+ s2_begin
+ s2_ff
+ s2_lock_relation
+ s1_sleep
+ s1_commit
+ s2_commit
+ s2_report_stat_lock_relation
+
+# transaction lock
+
+permutation
+ s1_set_deadlock_timeout
+ s1_reset_stat_lock
+ s1_set_log_lock_waits
+ s2_set_deadlock_timeout
+ s2_set_log_lock_waits
+ s1_table_insert
+ s1_begin
+ s1_table_update_k1
+ s2_begin
+ s2_ff
+ s2_table_update_k1
+ s1_sleep
+ s1_commit
+ s2_commit
+ s2_report_stat_lock_transactionid
+
+# advisory lock
+
+permutation
+ s1_set_deadlock_timeout
+ s1_reset_stat_lock
+ s1_set_log_lock_waits
+ s2_set_deadlock_timeout
+ s2_set_log_lock_waits
+ s1_lock_advisory_lock
+ s2_begin
+ s2_ff
+ s2_lock_advisory_lock
+ s1_sleep
+ s1_lock_advisory_unlock
+ s2_lock_advisory_unlock
+ s2_commit
+ s2_report_stat_lock_advisory
+
+# Ensure log_lock_waits behaves correctly
+
+permutation
+ s1_set_deadlock_timeout
+ s1_reset_stat_lock
+ s1_set_log_lock_waits
+ s2_set_deadlock_timeout
+ s2_unset_log_lock_waits
+ s1_begin
+ s1_lock_relation
+ s2_begin
+ s2_ff
+ s2_lock_relation
+ s1_sleep
+ s1_commit
+ s2_commit
+ s2_report_stat_lock_relation
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 78a37d9fc8f..2fcb48df6c9 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1951,6 +1951,13 @@ pg_stat_io| SELECT backend_type,
fsync_time,
stats_reset
FROM pg_stat_get_io() b(backend_type, object, context, reads, read_bytes, read_time, writes, write_bytes, write_time, writebacks, writeback_time, extends, extend_bytes, extend_time, hits, evictions, reuses, fsyncs, fsync_time, stats_reset);
+pg_stat_lock| SELECT locktype,
+ waits,
+ timed_waits,
+ wait_time,
+ fastpath_exceeded,
+ stats_reset
+ FROM pg_stat_get_lock() l(locktype, waits, timed_waits, wait_time, fastpath_exceeded, stats_reset);
pg_stat_progress_analyze| SELECT s.pid,
s.datid,
d.datname,
diff --git a/src/test/regress/expected/stats.out b/src/test/regress/expected/stats.out
index cd00f35bf7a..93de87747d4 100644
--- a/src/test/regress/expected/stats.out
+++ b/src/test/regress/expected/stats.out
@@ -1910,4 +1910,52 @@ SELECT * FROM check_estimated_rows('SELECT * FROM table_fillfactor');
(1 row)
DROP TABLE table_fillfactor;
+-- Test fastpath_exceeded stat
+CREATE TABLE part_test (id int) PARTITION BY RANGE (id);
+SELECT pg_stat_reset_shared('lock');
+ pg_stat_reset_shared
+----------------------
+
+(1 row)
+
+-- Create partitions (exceeds number of slots)
+DO $$
+DECLARE
+ max_locks int;
+BEGIN
+ SELECT setting::int INTO max_locks
+ FROM pg_settings
+ WHERE name = 'max_locks_per_transaction';
+
+ FOR i IN 1..(max_locks + 10) LOOP
+ EXECUTE format(
+ 'CREATE TABLE part_test_%s PARTITION OF part_test
+ FOR VALUES FROM (%s) TO (%s)',
+ i, (i-1)*1000, i*1000
+ );
+ END LOOP;
+END;
+$$;
+SELECT fastpath_exceeded AS fastpath_exceeded_before FROM pg_stat_lock WHERE locktype = 'relation' \gset
+-- Needs a lock on each partition
+SELECT count(*) FROM part_test;
+ count
+-------
+ 0
+(1 row)
+
+-- Ensure pending stats are flushed
+SELECT pg_stat_force_next_flush();
+ pg_stat_force_next_flush
+--------------------------
+
+(1 row)
+
+SELECT fastpath_exceeded > :fastpath_exceeded_before FROM pg_stat_lock WHERE locktype = 'relation';
+ ?column?
+----------
+ t
+(1 row)
+
+DROP TABLE part_test;
-- End of Stats Test
diff --git a/src/test/regress/sql/stats.sql b/src/test/regress/sql/stats.sql
index 8768e0f27fd..db9948eedb8 100644
--- a/src/test/regress/sql/stats.sql
+++ b/src/test/regress/sql/stats.sql
@@ -944,4 +944,40 @@ SELECT * FROM check_estimated_rows('SELECT * FROM table_fillfactor');
DROP TABLE table_fillfactor;
+-- Test fastpath_exceeded stat
+CREATE TABLE part_test (id int) PARTITION BY RANGE (id);
+
+SELECT pg_stat_reset_shared('lock');
+
+-- Create partitions (exceeds number of slots)
+DO $$
+DECLARE
+ max_locks int;
+BEGIN
+ SELECT setting::int INTO max_locks
+ FROM pg_settings
+ WHERE name = 'max_locks_per_transaction';
+
+ FOR i IN 1..(max_locks + 10) LOOP
+ EXECUTE format(
+ 'CREATE TABLE part_test_%s PARTITION OF part_test
+ FOR VALUES FROM (%s) TO (%s)',
+ i, (i-1)*1000, i*1000
+ );
+ END LOOP;
+END;
+$$;
+
+SELECT fastpath_exceeded AS fastpath_exceeded_before FROM pg_stat_lock WHERE locktype = 'relation' \gset
+
+-- Needs a lock on each partition
+SELECT count(*) FROM part_test;
+
+-- Ensure pending stats are flushed
+SELECT pg_stat_force_next_flush();
+
+SELECT fastpath_exceeded > :fastpath_exceeded_before FROM pg_stat_lock WHERE locktype = 'relation';
+
+DROP TABLE part_test;
+
-- End of Stats Test
--
2.34.1
>From 0ecc6d129ae387e8cafb56a033a9b49edc0b12f0 Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <[email protected]>
Date: Fri, 20 Feb 2026 06:13:28 +0000
Subject: [PATCH v7 3/3] Introduce a new track_lock_timing GUC
A new GUC (track_lock_timing) is added and defaults to on. If on, timed_waits and
wait_time counters are incremented if the session waited longer than deadlock_timeout
to acquire the lock. It's on by default, as this is the same idea as 2aac62be8cb.
---
doc/src/sgml/config.sgml | 19 ++
doc/src/sgml/monitoring.sgml | 4 +-
src/backend/storage/lmgr/proc.c | 165 ++++++++++--------
src/backend/utils/misc/guc_parameters.dat | 6 +
src/backend/utils/misc/postgresql.conf.sample | 1 +
src/include/pgstat.h | 1 +
src/test/isolation/expected/stats.out | 24 +--
src/test/isolation/expected/stats_1.out | 24 +--
src/test/isolation/specs/stats.spec | 24 +--
9 files changed, 153 insertions(+), 115 deletions(-)
7.5% doc/src/sgml/
48.4% src/backend/storage/lmgr/
35.8% src/test/isolation/expected/
6.0% src/test/isolation/specs/
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 20dbcaeb3ee..1e6778576ea 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -8841,6 +8841,25 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
</listitem>
</varlistentry>
+ <varlistentry id="guc-track-lock-timing" xreflabel="track_lock_timing">
+ <term><varname>track_lock_timing</varname> (<type>boolean</type>)
+ <indexterm>
+ <primary><varname>track_lock_timing</varname> configuration parameter</primary>
+ </indexterm>
+ </term>
+ <listitem>
+ <para>
+ Enables timing of lock waits. This parameter is on by default, as it tracks
+ only the timings for successful acquisitions that waited longer than
+ <xref linkend="guc-deadlock-timeout"/>. Lock timing information is
+ displayed in the <link linkend="monitoring-pg-stat-lock-view">
+ <structname>pg_stat_lock</structname></link> view.
+ Only superusers and users with the appropriate <literal>SET</literal>
+ privilege can change this setting.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry id="guc-track-wal-io-timing" xreflabel="track_wal_io_timing">
<term><varname>track_wal_io_timing</varname> (<type>boolean</type>)
<indexterm>
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index cfcb8189418..277275fdcb5 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -3193,7 +3193,7 @@ description | Waiting for a newly initialized WAL file to reach durable storage
</para>
<para>
Number of times a lock of this type had to wait because of a
- conflicting lock. Only incremented when <xref linkend="guc-log-lock-waits"/>
+ conflicting lock. Only incremented when <xref linkend="guc-track-lock-timing"/>
is enabled and the lock was successfully acquired after waiting longer
than <xref linkend="guc-deadlock-timeout"/>.
</para>
@@ -3207,7 +3207,7 @@ description | Waiting for a newly initialized WAL file to reach durable storage
</para>
<para>
Total time spent waiting for locks of this type, in milliseconds.
- Only incremented when <xref linkend="guc-log-lock-waits"/> is enabled and
+ Only incremented when <xref linkend="guc-track-lock-timing"/> is enabled and
the lock was successfully acquired after waiting longer than
<xref linkend="guc-deadlock-timeout"/>.
</para>
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index bee4a3c2b89..18e42959e96 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -62,6 +62,7 @@ int IdleInTransactionSessionTimeout = 0;
int TransactionTimeout = 0;
int IdleSessionTimeout = 0;
bool log_lock_waits = true;
+bool track_lock_timing = true;
/* Pointer to this process's PGPROC struct, if any */
PGPROC *MyProc = NULL;
@@ -1545,99 +1546,110 @@ ProcSleep(LOCALLOCK *locallock)
/*
* If awoken after the deadlock check interrupt has run, and
- * log_lock_waits is on, then report about the wait.
+ * log_lock_waits or track_lock_timing is on, then report or track
+ * about the wait.
*/
- if (log_lock_waits && deadlock_state != DS_NOT_YET_CHECKED)
+ if ((log_lock_waits || track_lock_timing) &&
+ deadlock_state != DS_NOT_YET_CHECKED)
{
- StringInfoData buf,
- lock_waiters_sbuf,
- lock_holders_sbuf;
- const char *modename;
long secs;
int usecs;
long msecs;
- int lockHoldersNum = 0;
- initStringInfo(&buf);
- initStringInfo(&lock_waiters_sbuf);
- initStringInfo(&lock_holders_sbuf);
-
- DescribeLockTag(&buf, &locallock->tag.lock);
- modename = GetLockmodeName(locallock->tag.lock.locktag_lockmethodid,
- lockmode);
TimestampDifference(get_timeout_start_time(DEADLOCK_TIMEOUT),
GetCurrentTimestamp(),
&secs, &usecs);
msecs = secs * 1000 + usecs / 1000;
usecs = usecs % 1000;
- /* Gather a list of all lock holders and waiters */
- LWLockAcquire(partitionLock, LW_SHARED);
- GetLockHoldersAndWaiters(locallock, &lock_holders_sbuf,
- &lock_waiters_sbuf, &lockHoldersNum);
- LWLockRelease(partitionLock);
-
- if (deadlock_state == DS_SOFT_DEADLOCK)
- ereport(LOG,
- (errmsg("process %d avoided deadlock for %s on %s by rearranging queue order after %ld.%03d ms",
- MyProcPid, modename, buf.data, msecs, usecs),
- (errdetail_log_plural("Process holding the lock: %s. Wait queue: %s.",
- "Processes holding the lock: %s. Wait queue: %s.",
- lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
- else if (deadlock_state == DS_HARD_DEADLOCK)
- {
- /*
- * This message is a bit redundant with the error that will be
- * reported subsequently, but in some cases the error report
- * might not make it to the log (eg, if it's caught by an
- * exception handler), and we want to ensure all long-wait
- * events get logged.
- */
- ereport(LOG,
- (errmsg("process %d detected deadlock while waiting for %s on %s after %ld.%03d ms",
- MyProcPid, modename, buf.data, msecs, usecs),
- (errdetail_log_plural("Process holding the lock: %s. Wait queue: %s.",
- "Processes holding the lock: %s. Wait queue: %s.",
- lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
- }
-
- if (myWaitStatus == PROC_WAIT_STATUS_WAITING)
- ereport(LOG,
- (errmsg("process %d still waiting for %s on %s after %ld.%03d ms",
- MyProcPid, modename, buf.data, msecs, usecs),
- (errdetail_log_plural("Process holding the lock: %s. Wait queue: %s.",
- "Processes holding the lock: %s. Wait queue: %s.",
- lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
- else if (myWaitStatus == PROC_WAIT_STATUS_OK)
- {
- /* Increment the timed lock statistics counters */
+ /* Increment the timed lock statistics counters */
+ if (track_lock_timing && myWaitStatus == PROC_WAIT_STATUS_OK)
pgstat_count_lock_timed_wait(locallock->tag.lock.locktag_type,
msecs);
- ereport(LOG,
- (errmsg("process %d acquired %s on %s after %ld.%03d ms",
- MyProcPid, modename, buf.data, msecs, usecs)));
- }
- else
+ if (log_lock_waits)
{
- Assert(myWaitStatus == PROC_WAIT_STATUS_ERROR);
-
- /*
- * Currently, the deadlock checker always kicks its own
- * process, which means that we'll only see
- * PROC_WAIT_STATUS_ERROR when deadlock_state ==
- * DS_HARD_DEADLOCK, and there's no need to print redundant
- * messages. But for completeness and future-proofing, print
- * a message if it looks like someone else kicked us off the
- * lock.
- */
- if (deadlock_state != DS_HARD_DEADLOCK)
+ StringInfoData buf,
+ lock_waiters_sbuf,
+ lock_holders_sbuf;
+ const char *modename;
+ int lockHoldersNum = 0;
+
+ initStringInfo(&buf);
+ initStringInfo(&lock_waiters_sbuf);
+ initStringInfo(&lock_holders_sbuf);
+
+ DescribeLockTag(&buf, &locallock->tag.lock);
+ modename = GetLockmodeName(locallock->tag.lock.locktag_lockmethodid,
+ lockmode);
+
+ /* Gather a list of all lock holders and waiters */
+ LWLockAcquire(partitionLock, LW_SHARED);
+ GetLockHoldersAndWaiters(locallock, &lock_holders_sbuf,
+ &lock_waiters_sbuf, &lockHoldersNum);
+ LWLockRelease(partitionLock);
+
+ if (deadlock_state == DS_SOFT_DEADLOCK)
ereport(LOG,
- (errmsg("process %d failed to acquire %s on %s after %ld.%03d ms",
+ (errmsg("process %d avoided deadlock for %s on %s by rearranging queue order after %ld.%03d ms",
MyProcPid, modename, buf.data, msecs, usecs),
(errdetail_log_plural("Process holding the lock: %s. Wait queue: %s.",
"Processes holding the lock: %s. Wait queue: %s.",
lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
+ else if (deadlock_state == DS_HARD_DEADLOCK)
+ {
+ /*
+ * This message is a bit redundant with the error that
+ * will be reported subsequently, but in some cases the
+ * error report might not make it to the log (eg, if it's
+ * caught by an exception handler), and we want to ensure
+ * all long-wait events get logged.
+ */
+ ereport(LOG,
+ (errmsg("process %d detected deadlock while waiting for %s on %s after %ld.%03d ms",
+ MyProcPid, modename, buf.data, msecs, usecs),
+ (errdetail_log_plural("Process holding the lock: %s. Wait queue: %s.",
+ "Processes holding the lock: %s. Wait queue: %s.",
+ lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
+ }
+
+ if (myWaitStatus == PROC_WAIT_STATUS_WAITING)
+ ereport(LOG,
+ (errmsg("process %d still waiting for %s on %s after %ld.%03d ms",
+ MyProcPid, modename, buf.data, msecs, usecs),
+ (errdetail_log_plural("Process holding the lock: %s. Wait queue: %s.",
+ "Processes holding the lock: %s. Wait queue: %s.",
+ lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
+
+ else if (myWaitStatus == PROC_WAIT_STATUS_OK)
+ ereport(LOG,
+ (errmsg("process %d acquired %s on %s after %ld.%03d ms",
+ MyProcPid, modename, buf.data, msecs, usecs)));
+ else
+ {
+ Assert(myWaitStatus == PROC_WAIT_STATUS_ERROR);
+
+ /*
+ * Currently, the deadlock checker always kicks its own
+ * process, which means that we'll only see
+ * PROC_WAIT_STATUS_ERROR when deadlock_state ==
+ * DS_HARD_DEADLOCK, and there's no need to print
+ * redundant messages. But for completeness and
+ * future-proofing, print a message if it looks like
+ * someone else kicked us off the lock.
+ */
+ if (deadlock_state != DS_HARD_DEADLOCK)
+ ereport(LOG,
+ (errmsg("process %d failed to acquire %s on %s after %ld.%03d ms",
+ MyProcPid, modename, buf.data, msecs, usecs),
+ (errdetail_log_plural("Process holding the lock: %s. Wait queue: %s.",
+ "Processes holding the lock: %s. Wait queue: %s.",
+ lockHoldersNum, lock_holders_sbuf.data, lock_waiters_sbuf.data))));
+ }
+
+ pfree(buf.data);
+ pfree(lock_holders_sbuf.data);
+ pfree(lock_waiters_sbuf.data);
}
/*
@@ -1645,14 +1657,13 @@ ProcSleep(LOCALLOCK *locallock)
* state so we don't print the above messages again.
*/
deadlock_state = DS_NO_DEADLOCK;
-
- pfree(buf.data);
- pfree(lock_holders_sbuf.data);
- pfree(lock_waiters_sbuf.data);
}
} while (myWaitStatus == PROC_WAIT_STATUS_WAITING);
- /* Count lock waits unconditionally, regardless of log_lock_waits */
+ /*
+ * Count lock waits unconditionally, regardless of log_lock_waits or
+ * track_lock_timing.
+ */
pgstat_count_lock_waits(locallock->tag.lock.locktag_type);
/*
diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat
index 9507778415d..c21e6c6ea4e 100644
--- a/src/backend/utils/misc/guc_parameters.dat
+++ b/src/backend/utils/misc/guc_parameters.dat
@@ -3110,6 +3110,12 @@
boot_val => 'false',
},
+{ name => 'track_lock_timing', type => 'bool', context => 'PGC_SUSET', group => 'STATS_CUMULATIVE',
+ short_desc => 'Collects timing statistics for lock acquisition.',
+ variable => 'track_lock_timing',
+ boot_val => 'true',
+},
+
{ name => 'track_wal_io_timing', type => 'bool', context => 'PGC_SUSET', group => 'STATS_CUMULATIVE',
short_desc => 'Collects timing statistics for WAL I/O activity.',
variable => 'track_wal_io_timing',
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index f938cc65a3a..8a3a704aaa5 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -685,6 +685,7 @@
#track_counts = on
#track_cost_delay_timing = off
#track_io_timing = off
+#track_lock_timing = on
#track_wal_io_timing = off
#track_functions = none # none, pl, all
#stats_fetch_consistency = cache # cache, none, snapshot
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index a4cc006794d..62a9dc1b35e 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -840,6 +840,7 @@ extern PgStat_WalStats *pgstat_fetch_stat_wal(void);
extern PGDLLIMPORT bool pgstat_track_counts;
extern PGDLLIMPORT int pgstat_track_functions;
extern PGDLLIMPORT int pgstat_fetch_consistency;
+extern PGDLLIMPORT bool track_lock_timing;
/*
diff --git a/src/test/isolation/expected/stats.out b/src/test/isolation/expected/stats.out
index 86d70a0705c..f9cd78f03b3 100644
--- a/src/test/isolation/expected/stats.out
+++ b/src/test/isolation/expected/stats.out
@@ -3752,7 +3752,7 @@ test_stat_func| 1|t |t
step s1_commit: COMMIT;
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_set_track_lock_timing s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
pg_stat_force_next_flush
------------------------
@@ -3765,9 +3765,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_track_lock_timing: SET track_lock_timing = on;
step s1_begin: BEGIN;
step s1_lock_relation: LOCK TABLE test_stat_tab;
step s2_begin: BEGIN;
@@ -3794,7 +3794,7 @@ t |t |t
(1 row)
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_table_insert s1_begin s1_table_update_k1 s2_begin s2_ff s2_table_update_k1 s1_sleep s1_commit s2_commit s2_report_stat_lock_transactionid
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_set_track_lock_timing s1_table_insert s1_begin s1_table_update_k1 s2_begin s2_ff s2_table_update_k1 s1_sleep s1_commit s2_commit s2_report_stat_lock_transactionid
pg_stat_force_next_flush
------------------------
@@ -3807,9 +3807,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_track_lock_timing: SET track_lock_timing = on;
step s1_table_insert: INSERT INTO test_stat_tab(key, value) VALUES('k1', 1), ('k2', 1), ('k3', 1);
step s1_begin: BEGIN;
step s1_table_update_k1: UPDATE test_stat_tab SET value = value + 1 WHERE key = 'k1';
@@ -3837,7 +3837,7 @@ t |t |t
(1 row)
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_lock_advisory_lock s2_begin s2_ff s2_lock_advisory_lock s1_sleep s1_lock_advisory_unlock s2_lock_advisory_unlock s2_commit s2_report_stat_lock_advisory
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_set_track_lock_timing s1_lock_advisory_lock s2_begin s2_ff s2_lock_advisory_lock s1_sleep s1_lock_advisory_unlock s2_lock_advisory_unlock s2_commit s2_report_stat_lock_advisory
pg_stat_force_next_flush
------------------------
@@ -3850,9 +3850,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_track_lock_timing: SET track_lock_timing = on;
step s1_lock_advisory_lock: SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
@@ -3899,7 +3899,7 @@ t |t |t
(1 row)
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_unset_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_unset_track_lock_timing s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
pg_stat_force_next_flush
------------------------
@@ -3912,9 +3912,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_unset_log_lock_waits: SET log_lock_waits = off;
+step s2_unset_track_lock_timing: SET track_lock_timing = off;
step s1_begin: BEGIN;
step s1_lock_relation: LOCK TABLE test_stat_tab;
step s2_begin: BEGIN;
diff --git a/src/test/isolation/expected/stats_1.out b/src/test/isolation/expected/stats_1.out
index 4e4c68b4525..955f6ff5ec0 100644
--- a/src/test/isolation/expected/stats_1.out
+++ b/src/test/isolation/expected/stats_1.out
@@ -3776,7 +3776,7 @@ test_stat_func| 1|t |t
step s1_commit: COMMIT;
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_set_track_lock_timing s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
pg_stat_force_next_flush
------------------------
@@ -3789,9 +3789,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_track_lock_timing: SET track_lock_timing = on;
step s1_begin: BEGIN;
step s1_lock_relation: LOCK TABLE test_stat_tab;
step s2_begin: BEGIN;
@@ -3818,7 +3818,7 @@ t |t |t
(1 row)
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_table_insert s1_begin s1_table_update_k1 s2_begin s2_ff s2_table_update_k1 s1_sleep s1_commit s2_commit s2_report_stat_lock_transactionid
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_set_track_lock_timing s1_table_insert s1_begin s1_table_update_k1 s2_begin s2_ff s2_table_update_k1 s1_sleep s1_commit s2_commit s2_report_stat_lock_transactionid
pg_stat_force_next_flush
------------------------
@@ -3831,9 +3831,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_track_lock_timing: SET track_lock_timing = on;
step s1_table_insert: INSERT INTO test_stat_tab(key, value) VALUES('k1', 1), ('k2', 1), ('k3', 1);
step s1_begin: BEGIN;
step s1_table_update_k1: UPDATE test_stat_tab SET value = value + 1 WHERE key = 'k1';
@@ -3861,7 +3861,7 @@ t |t |t
(1 row)
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_set_log_lock_waits s1_lock_advisory_lock s2_begin s2_ff s2_lock_advisory_lock s1_sleep s1_lock_advisory_unlock s2_lock_advisory_unlock s2_commit s2_report_stat_lock_advisory
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_set_track_lock_timing s1_lock_advisory_lock s2_begin s2_ff s2_lock_advisory_lock s1_sleep s1_lock_advisory_unlock s2_lock_advisory_unlock s2_commit s2_report_stat_lock_advisory
pg_stat_force_next_flush
------------------------
@@ -3874,9 +3874,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_set_log_lock_waits: SET log_lock_waits = on;
+step s2_set_track_lock_timing: SET track_lock_timing = on;
step s1_lock_advisory_lock: SELECT pg_advisory_lock(1);
pg_advisory_lock
----------------
@@ -3923,7 +3923,7 @@ t |t |t
(1 row)
-starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_log_lock_waits s2_set_deadlock_timeout s2_unset_log_lock_waits s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
+starting permutation: s1_set_deadlock_timeout s1_reset_stat_lock s1_set_track_lock_timing s2_set_deadlock_timeout s2_unset_track_lock_timing s1_begin s1_lock_relation s2_begin s2_ff s2_lock_relation s1_sleep s1_commit s2_commit s2_report_stat_lock_relation
pg_stat_force_next_flush
------------------------
@@ -3936,9 +3936,9 @@ pg_stat_reset_shared
(1 row)
-step s1_set_log_lock_waits: SET log_lock_waits = on;
+step s1_set_track_lock_timing: SET track_lock_timing = on;
step s2_set_deadlock_timeout: SET deadlock_timeout = '10ms';
-step s2_unset_log_lock_waits: SET log_lock_waits = off;
+step s2_unset_track_lock_timing: SET track_lock_timing = off;
step s1_begin: BEGIN;
step s1_lock_relation: LOCK TABLE test_stat_tab;
step s2_begin: BEGIN;
diff --git a/src/test/isolation/specs/stats.spec b/src/test/isolation/specs/stats.spec
index d4b53545198..7c8e2a9214e 100644
--- a/src/test/isolation/specs/stats.spec
+++ b/src/test/isolation/specs/stats.spec
@@ -132,7 +132,7 @@ step s1_slru_check_stats {
# Lock stats steps
step s1_set_deadlock_timeout { SET deadlock_timeout = '10ms'; }
-step s1_set_log_lock_waits { SET log_lock_waits = on; }
+step s1_set_track_lock_timing { SET track_lock_timing = on; }
step s1_reset_stat_lock { SELECT pg_stat_reset_shared('lock'); }
step s1_sleep { SELECT pg_sleep(0.5); }
step s1_lock_relation { LOCK TABLE test_stat_tab; }
@@ -174,8 +174,8 @@ step s2_big_notify { SELECT pg_notify('stats_test_use',
# Lock stats steps
step s2_set_deadlock_timeout { SET deadlock_timeout = '10ms'; }
-step s2_set_log_lock_waits { SET log_lock_waits = on; }
-step s2_unset_log_lock_waits { SET log_lock_waits = off; }
+step s2_set_track_lock_timing { SET track_lock_timing = on; }
+step s2_unset_track_lock_timing { SET track_lock_timing = off; }
step s2_report_stat_lock_relation { SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'relation'; }
step s2_report_stat_lock_transactionid { SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'transactionid'; }
step s2_report_stat_lock_advisory { SELECT waits > 0, timed_waits = waits, wait_time > 500 FROM pg_stat_lock WHERE locktype = 'advisory'; }
@@ -793,9 +793,9 @@ permutation
permutation
s1_set_deadlock_timeout
s1_reset_stat_lock
- s1_set_log_lock_waits
+ s1_set_track_lock_timing
s2_set_deadlock_timeout
- s2_set_log_lock_waits
+ s2_set_track_lock_timing
s1_begin
s1_lock_relation
s2_begin
@@ -811,9 +811,9 @@ permutation
permutation
s1_set_deadlock_timeout
s1_reset_stat_lock
- s1_set_log_lock_waits
+ s1_set_track_lock_timing
s2_set_deadlock_timeout
- s2_set_log_lock_waits
+ s2_set_track_lock_timing
s1_table_insert
s1_begin
s1_table_update_k1
@@ -830,9 +830,9 @@ permutation
permutation
s1_set_deadlock_timeout
s1_reset_stat_lock
- s1_set_log_lock_waits
+ s1_set_track_lock_timing
s2_set_deadlock_timeout
- s2_set_log_lock_waits
+ s2_set_track_lock_timing
s1_lock_advisory_lock
s2_begin
s2_ff
@@ -843,14 +843,14 @@ permutation
s2_commit
s2_report_stat_lock_advisory
-# Ensure log_lock_waits behaves correctly
+# Ensure track_lock_timing behaves correctly
permutation
s1_set_deadlock_timeout
s1_reset_stat_lock
- s1_set_log_lock_waits
+ s1_set_track_lock_timing
s2_set_deadlock_timeout
- s2_unset_log_lock_waits
+ s2_unset_track_lock_timing
s1_begin
s1_lock_relation
s2_begin
--
2.34.1
