Hi hackers,
Long running transactions can accumulate significant statistics (WAL, IO, ...)
that remain unflushed until the transaction ends. This delays visibility of
resource usage in monitoring views like pg_stat_io and pg_stat_wal.
This patch series introduce the ability to $SUBJECT (suggested in [1]) to:
- improve monitoring of long running transactions
- avoid missing places where we should flush statistics (like the one fixed in
039549d70f6)
The patch series is made of 3 sub-patches:
0001: Add pgstat_report_anytime_stat() for periodic stats flushing
It introduces pgstat_report_anytime_stat(), which flushes non transactional
statistics even inside active transactions. A new timeout handler fires every
second to call this function, ensuring timely stats visibility without waiting
for transaction completion.
Implementation details:
- Add PgStat_FlushBehavior enum to classify stats kinds:
* FLUSH_ANYTIME: Stats that can always be flushed (WAL, IO, ...)
* FLUSH_AT_TXN_BOUNDARY: Stats requiring transaction boundaries
- Modify pgstat_flush_pending_entries() and pgstat_flush_fixed_stats() to accept
a boolean anytime_only parameter:
* When false: flushes all stats (existing behavior)
* When true: flushes only FLUSH_ANYTIME stats and skips FLUSH_AT_TXN_BOUNDARY
stats
- Register ANYTIME_STATS_UPDATE_TIMEOUT that fires every 1 second, calling
pgstat_report_anytime_stat(false)
Remarks:
- The force parameter in pgstat_report_anytime_stat() is currently unused
(always
called with force=false) but reserved for future use cases requiring immediate
flushing.
The 1 second flush interval is currently hardcoded but we could imagine increase
it or make it configurable. I ran some benchmarks and did not notice any
noticeable
performance regression even with a large number of pending entries.
0002: Remove useless calls to flush some stats
Now that some stats can be flushed outside of transaction boundaries, remove
useless calls to flush some stats. Those calls were in place because
before 0001 stats were flushed only at transaction boundaries.
Remarks:
- it reverts 039549d70f6 (it just keeps its tests)
- it can't be done for checkpointer and bgworker for example because they don't
have a flush callback to call
- it can't be done for auxiliary process (walsummarizer for example) because
they
currently do not register the new timeout handler
- we may want to improve the current behavior to "fix" the 2 above
0003: Add FLUSH_MIXED support and implement it for RELATION stats
This patch extends the non transactional stats infrastructure to support
statistics
kinds with mixed transaction behavior: some fields are transactional (e.g.,
tuple
inserts/updates/deletes) while others are non transactional (e.g., sequential
scans
blocks read, ...).
It introduces FLUSH_MIXED as a third flush behavior type, alongside
FLUSH_ANYTIME
and FLUSH_AT_TXN_BOUNDARY. For FLUSH_MIXED kinds, a new flush_anytime_cb
callback
enables partial flushing of only the non transactional fields during running
transactions.
Some tests are also added.
Implementation details:
- Add FLUSH_MIXED to PgStat_FlushBehavior enum
- Add flush_anytime_cb to PgStat_KindInfo for partial flushing callback
- Update pgstat_flush_pending_entries() to call flush_anytime_cb for
FLUSH_MIXED entries when in anytime_only mode
- Keep FLUSH_MIXED entries in the pending list after partial flush, as
transactional fields still need to be flushed at transaction boundary
RELATION stats are making use of FLUSH_MIXED:
- Change RELATION from TXN_ALL to FLUSH_MIXED
- Implement pgstat_relation_flush_anytime_cb() to flush only read related
stats: numscans, tuples_returned, tuples_fetched, blocks_fetched,
blocks_hit
- Clear these fields after flushing to prevent double counting when
pgstat_relation_flush_cb() runs at transaction commit
- Transactional stats (tuples_inserted, tuples_updated, tuples_deleted,
live_tuples, dead_tuples) remain pending until transaction boundary
Remark:
We could also imagine adding a new flush_anytime_static_cb() callback for
future FLUSH_MIXED fixed amount stats.
[1]:
https://postgr.es/m/erpzwxoptqhuptdrtehqydzjapvroumkhh7lc6poclbhe7jk7l%40l3yfsq5q4pw7
Regards,
--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com
>From 2acc48f3c101b3230090abb53b0e05cc1d8af85f Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <[email protected]>
Date: Mon, 5 Jan 2026 09:41:39 +0000
Subject: [PATCH v1 1/3] Add pgstat_report_anytime_stat() for periodic stats
flushing
Long running transactions can accumulate significant statistics (WAL, IO, ...)
that remain unflushed until the transaction ends. This delays visibility of
resource usage in monitoring views like pg_stat_io and pg_stat_wal.
This commit introduces pgstat_report_anytime_stat(), which flushes
non transactional statistics even inside active transactions. A new timeout
handler fires every second to call this function, ensuring timely stats visibility
without waiting for transaction completion.
Implementation details:
- Add PgStat_FlushBehavior enum to classify stats kinds:
* FLUSH_ANYTIME: Stats that can always be flushed (WAL, IO, ...)
* FLUSH_AT_TXN_BOUNDARY: Stats requiring transaction boundaries
- Modify pgstat_flush_pending_entries() and pgstat_flush_fixed_stats()
to accept a boolean anytime_only parameter:
* When false: flushes all stats (existing behavior)
* When true: flushes only FLUSH_ANYTIME stats and skips FLUSH_AT_TXN_BOUNDARY stats
- Register ANYTIME_STATS_UPDATE_TIMEOUT that fires every 1 second, calling
pgstat_report_anytime_stat(false)
The force parameter in pgstat_report_anytime_stat() is currently unused (always
called with force=false) but reserved for future use cases requiring immediate
flushing.
---
src/backend/tcop/postgres.c | 18 +++++
src/backend/utils/activity/pgstat.c | 119 ++++++++++++++++++++++++----
src/backend/utils/init/globals.c | 1 +
src/backend/utils/init/postinit.c | 15 ++++
src/include/miscadmin.h | 1 +
src/include/pgstat.h | 4 +
src/include/utils/pgstat_internal.h | 11 +++
src/include/utils/timeout.h | 1 +
src/tools/pgindent/typedefs.list | 1 +
9 files changed, 154 insertions(+), 17 deletions(-)
9.7% src/backend/tcop/
70.2% src/backend/utils/activity/
9.3% src/backend/utils/init/
6.0% src/include/utils/
4.3% src/include/
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index e54bf1e760f..6a91543f80a 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3530,6 +3530,24 @@ ProcessInterrupts(void)
pgstat_report_stat(true);
}
+ /*
+ * Flush stats outside of transaction boundary if the timeout fired.
+ * Unlike transactional stats, these can be flushed even inside a running
+ * transaction.
+ */
+ if (AnytimeStatsUpdateTimeoutPending)
+ {
+ AnytimeStatsUpdateTimeoutPending = false;
+
+ /* Skip if completely idle */
+ if (!DoingCommandRead || IsTransactionOrTransactionBlock())
+ pgstat_report_anytime_stat(false);
+
+ /* Schedule next timeout */
+ enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT,
+ PGSTAT_ANYTIME_FLUSH_INTERVAL);
+ }
+
if (ProcSignalBarrierPending)
ProcessProcSignalBarrier();
diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c
index 11bb71cad5a..f7942e47475 100644
--- a/src/backend/utils/activity/pgstat.c
+++ b/src/backend/utils/activity/pgstat.c
@@ -187,7 +187,8 @@ static void pgstat_init_snapshot_fixed(void);
static void pgstat_reset_after_failure(void);
-static bool pgstat_flush_pending_entries(bool nowait);
+static bool pgstat_flush_pending_entries(bool nowait, bool anytime_only);
+static bool pgstat_flush_fixed_stats(bool nowait, bool anytime_only);
static void pgstat_prep_snapshot(void);
static void pgstat_build_snapshot(void);
@@ -288,6 +289,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = false,
.write_to_file = true,
+ .flush_behavior = FLUSH_AT_TXN_BOUNDARY,
/* so pg_stat_database entries can be seen in all databases */
.accessed_across_databases = true,
@@ -305,6 +307,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = false,
.write_to_file = true,
+ .flush_behavior = FLUSH_AT_TXN_BOUNDARY,
.shared_size = sizeof(PgStatShared_Relation),
.shared_data_off = offsetof(PgStatShared_Relation, stats),
@@ -321,6 +324,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = false,
.write_to_file = true,
+ .flush_behavior = FLUSH_AT_TXN_BOUNDARY,
.shared_size = sizeof(PgStatShared_Function),
.shared_data_off = offsetof(PgStatShared_Function, stats),
@@ -336,6 +340,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = false,
.write_to_file = true,
+ .flush_behavior = FLUSH_AT_TXN_BOUNDARY,
.accessed_across_databases = true,
@@ -353,6 +358,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = false,
.write_to_file = true,
+ .flush_behavior = FLUSH_AT_TXN_BOUNDARY,
/* so pg_stat_subscription_stats entries can be seen in all databases */
.accessed_across_databases = true,
@@ -370,6 +376,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = false,
.write_to_file = false,
+ .flush_behavior = FLUSH_ANYTIME,
.accessed_across_databases = true,
@@ -388,6 +395,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = true,
.write_to_file = true,
+ .flush_behavior = FLUSH_ANYTIME,
.snapshot_ctl_off = offsetof(PgStat_Snapshot, archiver),
.shared_ctl_off = offsetof(PgStat_ShmemControl, archiver),
@@ -404,6 +412,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = true,
.write_to_file = true,
+ .flush_behavior = FLUSH_ANYTIME,
.snapshot_ctl_off = offsetof(PgStat_Snapshot, bgwriter),
.shared_ctl_off = offsetof(PgStat_ShmemControl, bgwriter),
@@ -420,6 +429,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = true,
.write_to_file = true,
+ .flush_behavior = FLUSH_ANYTIME,
.snapshot_ctl_off = offsetof(PgStat_Snapshot, checkpointer),
.shared_ctl_off = offsetof(PgStat_ShmemControl, checkpointer),
@@ -436,6 +446,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = true,
.write_to_file = true,
+ .flush_behavior = FLUSH_ANYTIME,
.snapshot_ctl_off = offsetof(PgStat_Snapshot, io),
.shared_ctl_off = offsetof(PgStat_ShmemControl, io),
@@ -453,6 +464,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = true,
.write_to_file = true,
+ .flush_behavior = FLUSH_ANYTIME,
.snapshot_ctl_off = offsetof(PgStat_Snapshot, slru),
.shared_ctl_off = offsetof(PgStat_ShmemControl, slru),
@@ -470,6 +482,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = true,
.write_to_file = true,
+ .flush_behavior = FLUSH_ANYTIME,
.snapshot_ctl_off = offsetof(PgStat_Snapshot, wal),
.shared_ctl_off = offsetof(PgStat_ShmemControl, wal),
@@ -775,23 +788,11 @@ pgstat_report_stat(bool force)
partial_flush = false;
/* flush of variable-numbered stats tracked in pending entries list */
- partial_flush |= pgstat_flush_pending_entries(nowait);
+ partial_flush |= pgstat_flush_pending_entries(nowait, false);
/* flush of other stats kinds */
if (pgstat_report_fixed)
- {
- for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++)
- {
- const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind);
-
- if (!kind_info)
- continue;
- if (!kind_info->flush_static_cb)
- continue;
-
- partial_flush |= kind_info->flush_static_cb(nowait);
- }
- }
+ partial_flush |= pgstat_flush_fixed_stats(nowait, false);
last_flush = now;
@@ -1345,9 +1346,14 @@ pgstat_delete_pending_entry(PgStat_EntryRef *entry_ref)
/*
* Flush out pending variable-numbered stats.
+ *
+ * If anytime_only is true, only flushes FLUSH_ANYTIME entries.
+ * This is safe to call inside transactions.
+ *
+ * If anytime_only is false, flushes all entries.
*/
static bool
-pgstat_flush_pending_entries(bool nowait)
+pgstat_flush_pending_entries(bool nowait, bool anytime_only)
{
bool have_pending = false;
dlist_node *cur = NULL;
@@ -1377,6 +1383,20 @@ pgstat_flush_pending_entries(bool nowait)
Assert(!kind_info->fixed_amount);
Assert(kind_info->flush_pending_cb != NULL);
+ /* Skip transactional stats if we're in anytime_only mode */
+ if (anytime_only && kind_info->flush_behavior == FLUSH_AT_TXN_BOUNDARY)
+ {
+ have_pending = true;
+
+ if (dlist_has_next(&pgStatPending, cur))
+ next = dlist_next_node(&pgStatPending, cur);
+ else
+ next = NULL;
+
+ cur = next;
+ continue;
+ }
+
/* flush the stats, if possible */
did_flush = kind_info->flush_pending_cb(entry_ref, nowait);
@@ -1397,11 +1417,42 @@ pgstat_flush_pending_entries(bool nowait)
cur = next;
}
- Assert(dlist_is_empty(&pgStatPending) == !have_pending);
+ /*
+ * When in anytime_only mode, the list may not be empty because
+ * FLUSH_AT_TXN_BOUNDARY entries were skipped.
+ */
+ Assert(!anytime_only || dlist_is_empty(&pgStatPending) == !have_pending);
return have_pending;
}
+/*
+ * Flush fixed-amount stats.
+ *
+ * If anytime_only is true, only flushes FLUSH_ANYTIME stats (safe inside transactions).
+ * If anytime_only is false, flushes all stats with flush_static_cb.
+ */
+static bool
+pgstat_flush_fixed_stats(bool nowait, bool anytime_only)
+{
+ bool partial_flush = false;
+
+ for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++)
+ {
+ const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind);
+
+ if (!kind_info || !kind_info->flush_static_cb)
+ continue;
+
+ /* Skip transactional stats if we're in anytime_only mode */
+ if (anytime_only && kind_info->flush_behavior == FLUSH_AT_TXN_BOUNDARY)
+ continue;
+
+ partial_flush |= kind_info->flush_static_cb(nowait);
+ }
+
+ return partial_flush;
+}
/* ------------------------------------------------------------
* Helper / infrastructure functions
@@ -2119,3 +2170,37 @@ assign_stats_fetch_consistency(int newval, void *extra)
if (pgstat_fetch_consistency != newval)
force_stats_snapshot_clear = true;
}
+
+/*
+ * Flush non-transactional stats
+ *
+ * This is safe to call even inside a transaction. It only flushes stats
+ * kinds marked as FLUSH_ANYTIME.
+ *
+ * This allows long running transactions to report activity without waiting
+ * for transaction to finish.
+ */
+void
+pgstat_report_anytime_stat(bool force)
+{
+ bool nowait = !force;
+
+ pgstat_assert_is_up();
+
+ /*
+ * Exit if no pending stats at all. This avoids unnecessary work when
+ * backends are idle or in sessions without stats accumulation.
+ *
+ * Note: This check isn't precise as there might be only transactional
+ * stats pending, which we'll skip during the flush. However, maintaining
+ * precise tracking would add complexity that does not seem worth it from
+ * a performance point of view (no noticeable performance regression has
+ * been observed with the current implementation).
+ */
+ if (dlist_is_empty(&pgStatPending) && !pgstat_report_fixed)
+ return;
+
+ /* Flush stats outside of transaction boundary */
+ pgstat_flush_pending_entries(nowait, true);
+ pgstat_flush_fixed_stats(nowait, true);
+}
diff --git a/src/backend/utils/init/globals.c b/src/backend/utils/init/globals.c
index 36ad708b360..ad44826c39e 100644
--- a/src/backend/utils/init/globals.c
+++ b/src/backend/utils/init/globals.c
@@ -40,6 +40,7 @@ volatile sig_atomic_t IdleSessionTimeoutPending = false;
volatile sig_atomic_t ProcSignalBarrierPending = false;
volatile sig_atomic_t LogMemoryContextPending = false;
volatile sig_atomic_t IdleStatsUpdateTimeoutPending = false;
+volatile sig_atomic_t AnytimeStatsUpdateTimeoutPending = false;
volatile uint32 InterruptHoldoffCount = 0;
volatile uint32 QueryCancelHoldoffCount = 0;
volatile uint32 CritSectionCount = 0;
diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c
index 3f401faf3de..cb0f6aecad1 100644
--- a/src/backend/utils/init/postinit.c
+++ b/src/backend/utils/init/postinit.c
@@ -82,6 +82,7 @@ static void TransactionTimeoutHandler(void);
static void IdleSessionTimeoutHandler(void);
static void IdleStatsUpdateTimeoutHandler(void);
static void ClientCheckTimeoutHandler(void);
+static void AnytimeStatsUpdateTimeoutHandler(void);
static bool ThereIsAtLeastOneRole(void);
static void process_startup_options(Port *port, bool am_superuser);
static void process_settings(Oid databaseid, Oid roleid);
@@ -765,6 +766,9 @@ InitPostgres(const char *in_dbname, Oid dboid,
RegisterTimeout(CLIENT_CONNECTION_CHECK_TIMEOUT, ClientCheckTimeoutHandler);
RegisterTimeout(IDLE_STATS_UPDATE_TIMEOUT,
IdleStatsUpdateTimeoutHandler);
+ RegisterTimeout(ANYTIME_STATS_UPDATE_TIMEOUT,
+ AnytimeStatsUpdateTimeoutHandler);
+ enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_ANYTIME_FLUSH_INTERVAL);
}
/*
@@ -1446,3 +1450,14 @@ ThereIsAtLeastOneRole(void)
return result;
}
+
+/*
+ * Timeout handler for flushing non-transactional stats.
+ */
+static void
+AnytimeStatsUpdateTimeoutHandler(void)
+{
+ AnytimeStatsUpdateTimeoutPending = true;
+ InterruptPending = true;
+ SetLatch(MyLatch);
+}
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index db559b39c4d..8aeb9628871 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -96,6 +96,7 @@ extern PGDLLIMPORT volatile sig_atomic_t IdleSessionTimeoutPending;
extern PGDLLIMPORT volatile sig_atomic_t ProcSignalBarrierPending;
extern PGDLLIMPORT volatile sig_atomic_t LogMemoryContextPending;
extern PGDLLIMPORT volatile sig_atomic_t IdleStatsUpdateTimeoutPending;
+extern PGDLLIMPORT volatile sig_atomic_t AnytimeStatsUpdateTimeoutPending;
extern PGDLLIMPORT volatile sig_atomic_t CheckClientConnectionPending;
extern PGDLLIMPORT volatile sig_atomic_t ClientConnectionLost;
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index fff7ecc2533..86e65397614 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -35,6 +35,9 @@
/* Default directory to store temporary statistics data in */
#define PG_STAT_TMP_DIR "pg_stat_tmp"
+/* When to call pgstat_report_anytime_stat() again */
+#define PGSTAT_ANYTIME_FLUSH_INTERVAL 1000
+
/* Values for track_functions GUC variable --- order is significant! */
typedef enum TrackFunctionsLevel
{
@@ -533,6 +536,7 @@ extern void pgstat_initialize(void);
/* Functions called from backends */
extern long pgstat_report_stat(bool force);
+extern void pgstat_report_anytime_stat(bool force);
extern void pgstat_force_next_flush(void);
extern void pgstat_reset_counters(void);
diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h
index 9b8fbae00ed..02f4f13fc0f 100644
--- a/src/include/utils/pgstat_internal.h
+++ b/src/include/utils/pgstat_internal.h
@@ -224,6 +224,14 @@ typedef struct PgStat_SubXactStatus
PgStat_TableXactStatus *first; /* head of list for this subxact */
} PgStat_SubXactStatus;
+/*
+ * Flush behavior for statistics kinds.
+ */
+typedef enum PgStat_FlushBehavior
+{
+ FLUSH_ANYTIME, /* All fields can flush anytime */
+ FLUSH_AT_TXN_BOUNDARY, /* All fields need transaction boundary */
+} PgStat_FlushBehavior;
/*
* Metadata for a specific kind of statistics.
@@ -251,6 +259,9 @@ typedef struct PgStat_KindInfo
*/
bool track_entry_count:1;
+ /* Flush behavior */
+ PgStat_FlushBehavior flush_behavior;
+
/*
* The size of an entry in the shared stats hash table (pointed to by
* PgStatShared_HashEntry->body). For fixed-numbered statistics, this is
diff --git a/src/include/utils/timeout.h b/src/include/utils/timeout.h
index 0965b590b34..10723bb664c 100644
--- a/src/include/utils/timeout.h
+++ b/src/include/utils/timeout.h
@@ -35,6 +35,7 @@ typedef enum TimeoutId
IDLE_SESSION_TIMEOUT,
IDLE_STATS_UPDATE_TIMEOUT,
CLIENT_CONNECTION_CHECK_TIMEOUT,
+ ANYTIME_STATS_UPDATE_TIMEOUT,
STARTUP_PROGRESS_TIMEOUT,
/* First user-definable timeout reason */
USER_TIMEOUT,
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 09e7f1d420e..9aabb325f16 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2261,6 +2261,7 @@ PgStat_Counter
PgStat_EntryRef
PgStat_EntryRefHashEntry
PgStat_FetchConsistency
+PgStat_FlushBehavior
PgStat_FunctionCallUsage
PgStat_FunctionCounts
PgStat_HashKey
--
2.34.1
>From 2c9e50c45138319660c5aa6860873ffdeebb7a67 Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <[email protected]>
Date: Tue, 6 Jan 2026 11:06:31 +0000
Subject: [PATCH v1 2/3] Remove useless calls to flush some stats
Now that some stats can be flushed outside of transaction boundaries, remove
useless calls to report/flush some stats. Those calls were in place because
before commit <XXXX> stats were flushed only at transaction boundaries.
Note that:
- it reverts 039549d70f6 (it just keeps its tests)
- it can't be done for checkpointer and bgworker for example because they don't
have a flush callback to call
- it can't be done for auxiliary process (walsummarizer for example) because they
currently do not register the new timeout handler
---
src/backend/replication/walreceiver.c | 10 ------
src/backend/replication/walsender.c | 36 ++------------------
src/backend/utils/activity/pgstat_relation.c | 13 -------
3 files changed, 2 insertions(+), 57 deletions(-)
75.3% src/backend/replication/
24.6% src/backend/utils/activity/
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a41453530a1..266379c780a 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -553,16 +553,6 @@ WalReceiverMain(const void *startup_data, size_t startup_data_len)
*/
bool requestReply = false;
- /*
- * Report pending statistics to the cumulative stats
- * system. This location is useful for the report as it
- * is not within a tight loop in the WAL receiver, to
- * avoid bloating pgstats with requests, while also making
- * sure that the reports happen each time a status update
- * is sent.
- */
- pgstat_report_wal(false);
-
/*
* Check if time since last receive from primary has
* reached the configured limit.
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 1ab09655a70..c33185bd337 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -94,14 +94,10 @@
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/pg_lsn.h"
-#include "utils/pgstat_internal.h"
#include "utils/ps_status.h"
#include "utils/timeout.h"
#include "utils/timestamp.h"
-/* Minimum interval used by walsender for stats flushes, in ms */
-#define WALSENDER_STATS_FLUSH_INTERVAL 1000
-
/*
* Maximum data payload in a WAL data message. Must be >= XLOG_BLCKSZ.
*
@@ -1826,7 +1822,6 @@ WalSndWaitForWal(XLogRecPtr loc)
int wakeEvents;
uint32 wait_event = 0;
static XLogRecPtr RecentFlushPtr = InvalidXLogRecPtr;
- TimestampTz last_flush = 0;
/*
* Fast path to avoid acquiring the spinlock in case we already know we
@@ -1847,7 +1842,6 @@ WalSndWaitForWal(XLogRecPtr loc)
{
bool wait_for_standby_at_stop = false;
long sleeptime;
- TimestampTz now;
/* Clear any already-pending wakeups */
ResetLatch(MyLatch);
@@ -1958,8 +1952,7 @@ WalSndWaitForWal(XLogRecPtr loc)
* new WAL to be generated. (But if we have nothing to send, we don't
* want to wake on socket-writable.)
*/
- now = GetCurrentTimestamp();
- sleeptime = WalSndComputeSleeptime(now);
+ sleeptime = WalSndComputeSleeptime(GetCurrentTimestamp());
wakeEvents = WL_SOCKET_READABLE;
@@ -1968,15 +1961,6 @@ WalSndWaitForWal(XLogRecPtr loc)
Assert(wait_event != 0);
- /* Report IO statistics, if needed */
- if (TimestampDifferenceExceeds(last_flush, now,
- WALSENDER_STATS_FLUSH_INTERVAL))
- {
- pgstat_flush_io(false);
- (void) pgstat_flush_backend(false, PGSTAT_BACKEND_FLUSH_IO);
- last_flush = now;
- }
-
WalSndWait(wakeEvents, sleeptime, wait_event);
}
@@ -2879,8 +2863,6 @@ WalSndCheckTimeOut(void)
static void
WalSndLoop(WalSndSendDataCallback send_data)
{
- TimestampTz last_flush = 0;
-
/*
* Initialize the last reply timestamp. That enables timeout processing
* from hereon.
@@ -2975,9 +2957,6 @@ WalSndLoop(WalSndSendDataCallback send_data)
* WalSndWaitForWal() handle any other blocking; idle receivers need
* its additional actions. For physical replication, also block if
* caught up; its send_data does not block.
- *
- * The IO statistics are reported in WalSndWaitForWal() for the
- * logical WAL senders.
*/
if ((WalSndCaughtUp && send_data != XLogSendLogical &&
!streamingDoneSending) ||
@@ -2985,7 +2964,6 @@ WalSndLoop(WalSndSendDataCallback send_data)
{
long sleeptime;
int wakeEvents;
- TimestampTz now;
if (!streamingDoneReceiving)
wakeEvents = WL_SOCKET_READABLE;
@@ -2996,21 +2974,11 @@ WalSndLoop(WalSndSendDataCallback send_data)
* Use fresh timestamp, not last_processing, to reduce the chance
* of reaching wal_sender_timeout before sending a keepalive.
*/
- now = GetCurrentTimestamp();
- sleeptime = WalSndComputeSleeptime(now);
+ sleeptime = WalSndComputeSleeptime(GetCurrentTimestamp());
if (pq_is_send_pending())
wakeEvents |= WL_SOCKET_WRITEABLE;
- /* Report IO statistics, if needed */
- if (TimestampDifferenceExceeds(last_flush, now,
- WALSENDER_STATS_FLUSH_INTERVAL))
- {
- pgstat_flush_io(false);
- (void) pgstat_flush_backend(false, PGSTAT_BACKEND_FLUSH_IO);
- last_flush = now;
- }
-
/* Sleep until something happens or we time out */
WalSndWait(wakeEvents, sleeptime, WAIT_EVENT_WAL_SENDER_MAIN);
}
diff --git a/src/backend/utils/activity/pgstat_relation.c b/src/backend/utils/activity/pgstat_relation.c
index bc8c43b96aa..feae2ae5f44 100644
--- a/src/backend/utils/activity/pgstat_relation.c
+++ b/src/backend/utils/activity/pgstat_relation.c
@@ -260,15 +260,6 @@ pgstat_report_vacuum(Relation rel, PgStat_Counter livetuples,
}
pgstat_unlock_entry(entry_ref);
-
- /*
- * Flush IO statistics now. pgstat_report_stat() will flush IO stats,
- * however this will not be called until after an entire autovacuum cycle
- * is done -- which will likely vacuum many relations -- or until the
- * VACUUM command has processed all tables and committed.
- */
- pgstat_flush_io(false);
- (void) pgstat_flush_backend(false, PGSTAT_BACKEND_FLUSH_IO);
}
/*
@@ -360,10 +351,6 @@ pgstat_report_analyze(Relation rel,
}
pgstat_unlock_entry(entry_ref);
-
- /* see pgstat_report_vacuum() */
- pgstat_flush_io(false);
- (void) pgstat_flush_backend(false, PGSTAT_BACKEND_FLUSH_IO);
}
/*
--
2.34.1
>From af71e6472727b4e18ca369e21e2b4667d4cd172b Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <[email protected]>
Date: Thu, 8 Jan 2026 09:17:38 +0000
Subject: [PATCH v1 3/3] Add FLUSH_MIXED support and implement it for RELATION
stats
This commit extends the non transactional stats infrastructure to support statistics
kinds with mixed transaction behavior: some fields are transactional (e.g., tuple
inserts/updates/deletes) while others are non transactional (e.g., sequential scans
blocks read, ...).
It introduces FLUSH_MIXED as a third flush behavior type, alongside FLUSH_ANYTIME
and FLUSH_AT_TXN_BOUNDARY. For FLUSH_MIXED kinds, a new flush_anytime_cb callback
enables partial flushing of only the non transactional fields during running
transactions.
Some tests are also added.
Implementation details:
- Add FLUSH_MIXED to PgStat_FlushBehavior enum
- Add flush_anytime_cb to PgStat_KindInfo for partial flushing callback
- Update pgstat_flush_pending_entries() to call flush_anytime_cb for
FLUSH_MIXED entries when in anytime_only mode
- Keep FLUSH_MIXED entries in the pending list after partial flush, as
transactional fields still need to be flushed at transaction boundary
RELATION stats are making use of FLUSH_MIXED:
- Change RELATION from TXN_ALL to FLUSH_MIXED
- Implement pgstat_relation_flush_anytime_cb() to flush only read related
stats: numscans, tuples_returned, tuples_fetched, blocks_fetched,
blocks_hit
- Clear these fields after flushing to prevent double counting when
pgstat_relation_flush_cb() runs at transaction commit
- Transactional stats (tuples_inserted, tuples_updated, tuples_deleted,
live_tuples, dead_tuples) remain pending until transaction boundary
Remark:
We could also imagine adding a new flush_anytime_static_cb() callback for
future FLUSH_MIXED fixed amount stats.
---
src/backend/utils/activity/pgstat.c | 36 ++++++---
src/backend/utils/activity/pgstat_relation.c | 82 ++++++++++++++++++++
src/include/utils/pgstat_internal.h | 8 ++
src/test/isolation/expected/stats.out | 40 ++++++++++
src/test/isolation/expected/stats_1.out | 40 ++++++++++
src/test/isolation/specs/stats.spec | 12 +++
6 files changed, 209 insertions(+), 9 deletions(-)
56.6% src/backend/utils/activity/
4.7% src/include/utils/
34.0% src/test/isolation/expected/
4.6% src/test/isolation/specs/
diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c
index f7942e47475..191e0ceac88 100644
--- a/src/backend/utils/activity/pgstat.c
+++ b/src/backend/utils/activity/pgstat.c
@@ -307,7 +307,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.fixed_amount = false,
.write_to_file = true,
- .flush_behavior = FLUSH_AT_TXN_BOUNDARY,
+ .flush_behavior = FLUSH_MIXED,
.shared_size = sizeof(PgStatShared_Relation),
.shared_data_off = offsetof(PgStatShared_Relation, stats),
@@ -315,6 +315,7 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
.pending_size = sizeof(PgStat_TableStatus),
.flush_pending_cb = pgstat_relation_flush_cb,
+ .flush_anytime_cb = pgstat_relation_flush_anytime_cb,
.delete_pending_cb = pgstat_relation_delete_pending_cb,
.reset_timestamp_cb = pgstat_relation_reset_timestamp_cb,
},
@@ -1347,10 +1348,11 @@ pgstat_delete_pending_entry(PgStat_EntryRef *entry_ref)
/*
* Flush out pending variable-numbered stats.
*
- * If anytime_only is true, only flushes FLUSH_ANYTIME entries.
+ * If anytime_only is true, only flushes FLUSH_ANYTIME and FLUSH_MIXED entries,
+ * using flush_anytime_cb for FLUSH_MIXED.
* This is safe to call inside transactions.
*
- * If anytime_only is false, flushes all entries.
+ * If anytime_only is false, flushes all entries using flush_pending_cb.
*/
static bool
pgstat_flush_pending_entries(bool nowait, bool anytime_only)
@@ -1378,6 +1380,7 @@ pgstat_flush_pending_entries(bool nowait, bool anytime_only)
PgStat_Kind kind = key.kind;
const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind);
bool did_flush;
+ bool is_partial_flush = false;
dlist_node *next;
Assert(!kind_info->fixed_amount);
@@ -1397,8 +1400,21 @@ pgstat_flush_pending_entries(bool nowait, bool anytime_only)
continue;
}
- /* flush the stats, if possible */
- did_flush = kind_info->flush_pending_cb(entry_ref, nowait);
+ /* flush the stats (with the appropriate callback), if possible */
+ if (anytime_only &&
+ kind_info->flush_behavior == FLUSH_MIXED &&
+ kind_info->flush_anytime_cb != NULL)
+ {
+ /* Partial flush of non-transactional fields only */
+ did_flush = kind_info->flush_anytime_cb(entry_ref, nowait);
+ is_partial_flush = true;
+ }
+ else
+ {
+ /* Full flush */
+ did_flush = kind_info->flush_pending_cb(entry_ref, nowait);
+ is_partial_flush = false;
+ }
Assert(did_flush || nowait);
@@ -1408,8 +1424,8 @@ pgstat_flush_pending_entries(bool nowait, bool anytime_only)
else
next = NULL;
- /* if successfully flushed, remove entry */
- if (did_flush)
+ /* if successfull non partial flush, remove entry */
+ if (did_flush && !is_partial_flush)
pgstat_delete_pending_entry(entry_ref);
else
have_pending = true;
@@ -1418,8 +1434,10 @@ pgstat_flush_pending_entries(bool nowait, bool anytime_only)
}
/*
- * When in anytime_only mode, the list may not be empty because
- * FLUSH_AT_TXN_BOUNDARY entries were skipped.
+ * When in anytime_only mode, the list may not be empty even after
+ * successful flushes because FLUSH_AT_TXN_BOUNDARY entries were skipped
+ * or FLUSH_MIXED entries had partial flushes and remain for transaction
+ * boundary.
*/
Assert(!anytime_only || dlist_is_empty(&pgStatPending) == !have_pending);
diff --git a/src/backend/utils/activity/pgstat_relation.c b/src/backend/utils/activity/pgstat_relation.c
index feae2ae5f44..6d6f333039e 100644
--- a/src/backend/utils/activity/pgstat_relation.c
+++ b/src/backend/utils/activity/pgstat_relation.c
@@ -887,6 +887,88 @@ pgstat_relation_flush_cb(PgStat_EntryRef *entry_ref, bool nowait)
return true;
}
+/*
+ * Flush only non-transactional relation stats.
+ *
+ * This is called periodically during running transactions to make some
+ * statistics visible without waiting for the transaction to finish.
+ *
+ * Transactional stats (inserts/updates/deletes and their effects on live/dead
+ * tuple counts) remain in pending until the transaction ends, at which point
+ * pgstat_relation_flush_cb() will flush them.
+ *
+ * If nowait is true and the lock could not be immediately acquired, returns
+ * false without flushing the entry. Otherwise returns true.
+ */
+bool
+pgstat_relation_flush_anytime_cb(PgStat_EntryRef *entry_ref, bool nowait)
+{
+ Oid dboid;
+ PgStat_TableStatus *lstats; /* pending stats entry */
+ PgStatShared_Relation *shtabstats;
+ PgStat_StatTabEntry *tabentry; /* table entry of shared stats */
+ PgStat_StatDBEntry *dbentry; /* pending database entry */
+ bool has_nontxn_stats = false;
+
+ dboid = entry_ref->shared_entry->key.dboid;
+ lstats = (PgStat_TableStatus *) entry_ref->pending;
+ shtabstats = (PgStatShared_Relation *) entry_ref->shared_stats;
+
+ /*
+ * Check if there are any non-transactional stats to flush. Avoid
+ * unnecessarily locking the entry if nothing accumulated.
+ */
+ if (lstats->counts.numscans > 0 ||
+ lstats->counts.tuples_returned > 0 ||
+ lstats->counts.tuples_fetched > 0 ||
+ lstats->counts.blocks_fetched > 0 ||
+ lstats->counts.blocks_hit > 0)
+ has_nontxn_stats = true;
+
+ if (!has_nontxn_stats)
+ return true;
+
+ if (!pgstat_lock_entry(entry_ref, nowait))
+ return false;
+
+ /* Add only the non-transactional values to the shared entry */
+ tabentry = &shtabstats->stats;
+
+ tabentry->numscans += lstats->counts.numscans;
+ if (lstats->counts.numscans)
+ {
+ TimestampTz t = GetCurrentTimestamp();
+
+ if (t > tabentry->lastscan)
+ tabentry->lastscan = t;
+ }
+ tabentry->tuples_returned += lstats->counts.tuples_returned;
+ tabentry->tuples_fetched += lstats->counts.tuples_fetched;
+ tabentry->blocks_fetched += lstats->counts.blocks_fetched;
+ tabentry->blocks_hit += lstats->counts.blocks_hit;
+
+ pgstat_unlock_entry(entry_ref);
+
+ /* Also update the corresponding fields in database stats */
+ dbentry = pgstat_prep_database_pending(dboid);
+ dbentry->tuples_returned += lstats->counts.tuples_returned;
+ dbentry->tuples_fetched += lstats->counts.tuples_fetched;
+ dbentry->blocks_fetched += lstats->counts.blocks_fetched;
+ dbentry->blocks_hit += lstats->counts.blocks_hit;
+
+ /*
+ * Clear the flushed fields from pending stats to prevent double-counting
+ * when pgstat_relation_flush_cb() runs at transaction boundary.
+ */
+ lstats->counts.numscans = 0;
+ lstats->counts.tuples_returned = 0;
+ lstats->counts.tuples_fetched = 0;
+ lstats->counts.blocks_fetched = 0;
+ lstats->counts.blocks_hit = 0;
+
+ return true;
+}
+
void
pgstat_relation_delete_pending_cb(PgStat_EntryRef *entry_ref)
{
diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h
index 02f4f13fc0f..85d92f4c945 100644
--- a/src/include/utils/pgstat_internal.h
+++ b/src/include/utils/pgstat_internal.h
@@ -231,6 +231,7 @@ typedef enum PgStat_FlushBehavior
{
FLUSH_ANYTIME, /* All fields can flush anytime */
FLUSH_AT_TXN_BOUNDARY, /* All fields need transaction boundary */
+ FLUSH_MIXED, /* MIXED so needs callbacks */
} PgStat_FlushBehavior;
/*
@@ -262,6 +263,12 @@ typedef struct PgStat_KindInfo
/* Flush behavior */
PgStat_FlushBehavior flush_behavior;
+ /*
+ * For PGSTAT_FLUSH_MIXED kinds: callback to flush only some fields. If
+ * NULL for a MIXED kind, treated as PGSTAT_FLUSH_AT_TXN_BOUNDARY.
+ */
+ bool (*flush_anytime_cb) (PgStat_EntryRef *entry_ref, bool nowait);
+
/*
* The size of an entry in the shared stats hash table (pointed to by
* PgStatShared_HashEntry->body). For fixed-numbered statistics, this is
@@ -774,6 +781,7 @@ extern void AtPrepare_PgStat_Relations(PgStat_SubXactStatus *xact_state);
extern void PostPrepare_PgStat_Relations(PgStat_SubXactStatus *xact_state);
extern bool pgstat_relation_flush_cb(PgStat_EntryRef *entry_ref, bool nowait);
+extern bool pgstat_relation_flush_anytime_cb(PgStat_EntryRef *entry_ref, bool nowait);
extern void pgstat_relation_delete_pending_cb(PgStat_EntryRef *entry_ref);
extern void pgstat_relation_reset_timestamp_cb(PgStatShared_Common *header, TimestampTz ts);
diff --git a/src/test/isolation/expected/stats.out b/src/test/isolation/expected/stats.out
index cfad309ccf3..6d62b30e4a7 100644
--- a/src/test/isolation/expected/stats.out
+++ b/src/test/isolation/expected/stats.out
@@ -2245,6 +2245,46 @@ seq_scan|seq_tup_read|n_tup_ins|n_tup_upd|n_tup_del|n_live_tup|n_dead_tup|vacuum
(1 row)
+starting permutation: s2_begin s2_table_select s1_sleep s1_table_stats s2_table_drop s2_commit
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_begin: BEGIN;
+step s2_table_select: SELECT * FROM test_stat_tab ORDER BY key, value;
+key|value
+---+-----
+k0 | 1
+(1 row)
+
+step s1_sleep: SELECT pg_sleep(1.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_table_stats:
+ SELECT
+ pg_stat_get_numscans(tso.oid) AS seq_scan,
+ pg_stat_get_tuples_returned(tso.oid) AS seq_tup_read,
+ pg_stat_get_tuples_inserted(tso.oid) AS n_tup_ins,
+ pg_stat_get_tuples_updated(tso.oid) AS n_tup_upd,
+ pg_stat_get_tuples_deleted(tso.oid) AS n_tup_del,
+ pg_stat_get_live_tuples(tso.oid) AS n_live_tup,
+ pg_stat_get_dead_tuples(tso.oid) AS n_dead_tup,
+ pg_stat_get_vacuum_count(tso.oid) AS vacuum_count
+ FROM test_stat_oid AS tso
+ WHERE tso.name = 'test_stat_tab'
+
+seq_scan|seq_tup_read|n_tup_ins|n_tup_upd|n_tup_del|n_live_tup|n_dead_tup|vacuum_count
+--------+------------+---------+---------+---------+----------+----------+------------
+ 1| 1| 1| 0| 0| 1| 0| 0
+(1 row)
+
+step s2_table_drop: DROP TABLE test_stat_tab;
+step s2_commit: COMMIT;
+
starting permutation: s1_track_counts_off s1_table_stats s1_track_counts_on
pg_stat_force_next_flush
------------------------
diff --git a/src/test/isolation/expected/stats_1.out b/src/test/isolation/expected/stats_1.out
index e1d937784cb..2fade10e817 100644
--- a/src/test/isolation/expected/stats_1.out
+++ b/src/test/isolation/expected/stats_1.out
@@ -2253,6 +2253,46 @@ seq_scan|seq_tup_read|n_tup_ins|n_tup_upd|n_tup_del|n_live_tup|n_dead_tup|vacuum
(1 row)
+starting permutation: s2_begin s2_table_select s1_sleep s1_table_stats s2_table_drop s2_commit
+pg_stat_force_next_flush
+------------------------
+
+(1 row)
+
+step s2_begin: BEGIN;
+step s2_table_select: SELECT * FROM test_stat_tab ORDER BY key, value;
+key|value
+---+-----
+k0 | 1
+(1 row)
+
+step s1_sleep: SELECT pg_sleep(1.5);
+pg_sleep
+--------
+
+(1 row)
+
+step s1_table_stats:
+ SELECT
+ pg_stat_get_numscans(tso.oid) AS seq_scan,
+ pg_stat_get_tuples_returned(tso.oid) AS seq_tup_read,
+ pg_stat_get_tuples_inserted(tso.oid) AS n_tup_ins,
+ pg_stat_get_tuples_updated(tso.oid) AS n_tup_upd,
+ pg_stat_get_tuples_deleted(tso.oid) AS n_tup_del,
+ pg_stat_get_live_tuples(tso.oid) AS n_live_tup,
+ pg_stat_get_dead_tuples(tso.oid) AS n_dead_tup,
+ pg_stat_get_vacuum_count(tso.oid) AS vacuum_count
+ FROM test_stat_oid AS tso
+ WHERE tso.name = 'test_stat_tab'
+
+seq_scan|seq_tup_read|n_tup_ins|n_tup_upd|n_tup_del|n_live_tup|n_dead_tup|vacuum_count
+--------+------------+---------+---------+---------+----------+----------+------------
+ 0| 0| 1| 0| 0| 1| 0| 0
+(1 row)
+
+step s2_table_drop: DROP TABLE test_stat_tab;
+step s2_commit: COMMIT;
+
starting permutation: s1_track_counts_off s1_table_stats s1_track_counts_on
pg_stat_force_next_flush
------------------------
diff --git a/src/test/isolation/specs/stats.spec b/src/test/isolation/specs/stats.spec
index da16710da0f..1b0168e6176 100644
--- a/src/test/isolation/specs/stats.spec
+++ b/src/test/isolation/specs/stats.spec
@@ -50,6 +50,8 @@ step s1_rollback { ROLLBACK; }
step s1_prepare_a { PREPARE TRANSACTION 'a'; }
step s1_commit_prepared_a { COMMIT PREPARED 'a'; }
step s1_rollback_prepared_a { ROLLBACK PREPARED 'a'; }
+# Has to be greater than PGSTAT_ANYTIME_FLUSH_INTERVAL
+step s1_sleep { SELECT pg_sleep(1.5); }
# Function stats steps
step s1_ff { SELECT pg_stat_force_next_flush(); }
@@ -138,6 +140,7 @@ step s2_commit { COMMIT; }
step s2_commit_prepared_a { COMMIT PREPARED 'a'; }
step s2_rollback_prepared_a { ROLLBACK PREPARED 'a'; }
step s2_ff { SELECT pg_stat_force_next_flush(); }
+step s2_table_drop { DROP TABLE test_stat_tab; }
# Function stats steps
step s2_track_funcs_all { SET track_functions = 'all'; }
@@ -435,6 +438,15 @@ permutation
s1_table_drop
s1_table_stats
+### Check that some stats are updated (seq_scan and seq_tup_read)
+### while the transaction is still running
+permutation
+ s2_begin
+ s2_table_select
+ s1_sleep
+ s1_table_stats
+ s2_table_drop
+ s2_commit
### Check that we don't count changes with track counts off, but allow access
### to prior stats
--
2.34.1
