Hi,
On Wed, Feb 19, 2025 at 07:28:49AM +0900, Michael Paquier wrote:
> On Tue, Feb 18, 2025 at 10:45:29AM +0000, Bertrand Drouvot wrote:
> > Agree, done that way in the dedicated thread ([1]).
> >
> > [1]:
> > https://www.postgresql.org/message-id/flat/Z7RkQ0EfYaqqjgz/%40ip-10-97-1-34.eu-west-3.compute.internal
>
> Thanks for splitting this part into its own thread.
Now that 2421e9a51d2 is in, let's resume working in this thread. PFA a rebase to
make the CF bot happy. Nothing has changed since V7, V8 only removes "v7-0001" (
as part of 2421e9a51d2), so that v8-000N is nothing but v7-000(N+1).
Regards,
--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com
>From a4a1dce54b8542c74e39117e77b2f1d005341501 Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <bertranddrouvot...@gmail.com>
Date: Mon, 6 Jan 2025 07:51:27 +0000
Subject: [PATCH v8 1/3] Extract logic filling pg_stat_get_wal()'s tuple into
its own routine
This commit adds pg_stat_wal_build_tuple(), a helper routine for
pg_stat_get_wal(), that fills its tuple based on the contents
of PgStat_WalStats. This will be used in a follow-up commit that uses
the same structures as pg_stat_wal for reporting, but for the PGSTAT_KIND_BACKEND
statistics kind.
---
src/backend/utils/adt/pgstatfuncs.c | 48 +++++++++++++++++++----------
1 file changed, 32 insertions(+), 16 deletions(-)
100.0% src/backend/utils/adt/
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 68e16e52ab6..620d60a0938 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -1632,20 +1632,22 @@ pg_stat_get_backend_io(PG_FUNCTION_ARGS)
}
/*
- * Returns statistics of WAL activity
+ * pg_stat_wal_build_tuple
+ *
+ * Helper routine for pg_stat_get_wal() returning one tuple based on the contents
+ * of wal_stats.
*/
-Datum
-pg_stat_get_wal(PG_FUNCTION_ARGS)
+static Datum
+pg_stat_wal_build_tuple(PgStat_WalStats wal_stats)
{
-#define PG_STAT_GET_WAL_COLS 5
+#define PG_STAT_WAL_COLS 5
TupleDesc tupdesc;
- Datum values[PG_STAT_GET_WAL_COLS] = {0};
- bool nulls[PG_STAT_GET_WAL_COLS] = {0};
+ Datum values[PG_STAT_WAL_COLS] = {0};
+ bool nulls[PG_STAT_WAL_COLS] = {0};
char buf[256];
- PgStat_WalStats *wal_stats;
/* Initialise attributes information in the tuple descriptor */
- tupdesc = CreateTemplateTupleDesc(PG_STAT_GET_WAL_COLS);
+ tupdesc = CreateTemplateTupleDesc(PG_STAT_WAL_COLS);
TupleDescInitEntry(tupdesc, (AttrNumber) 1, "wal_records",
INT8OID, -1, 0);
TupleDescInitEntry(tupdesc, (AttrNumber) 2, "wal_fpi",
@@ -1659,28 +1661,42 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
BlessTupleDesc(tupdesc);
- /* Get statistics about WAL activity */
- wal_stats = pgstat_fetch_stat_wal();
-
/* Fill values and NULLs */
- values[0] = Int64GetDatum(wal_stats->wal_records);
- values[1] = Int64GetDatum(wal_stats->wal_fpi);
+ values[0] = Int64GetDatum(wal_stats.wal_records);
+ values[1] = Int64GetDatum(wal_stats.wal_fpi);
/* Convert to numeric. */
- snprintf(buf, sizeof buf, UINT64_FORMAT, wal_stats->wal_bytes);
+ snprintf(buf, sizeof buf, UINT64_FORMAT, wal_stats.wal_bytes);
values[2] = DirectFunctionCall3(numeric_in,
CStringGetDatum(buf),
ObjectIdGetDatum(0),
Int32GetDatum(-1));
- values[3] = Int64GetDatum(wal_stats->wal_buffers_full);
+ values[3] = Int64GetDatum(wal_stats.wal_buffers_full);
- values[4] = TimestampTzGetDatum(wal_stats->stat_reset_timestamp);
+ if (wal_stats.stat_reset_timestamp != 0)
+ values[4] = TimestampTzGetDatum(wal_stats.stat_reset_timestamp);
+ else
+ nulls[4] = true;
/* Returns the record as Datum */
PG_RETURN_DATUM(HeapTupleGetDatum(heap_form_tuple(tupdesc, values, nulls)));
}
+/*
+ * Returns statistics of WAL activity
+ */
+Datum
+pg_stat_get_wal(PG_FUNCTION_ARGS)
+{
+ PgStat_WalStats *wal_stats;
+
+ /* Get statistics about WAL activity */
+ wal_stats = pgstat_fetch_stat_wal();
+
+ return (pg_stat_wal_build_tuple(*wal_stats));
+}
+
/*
* Returns statistics of SLRU caches.
*/
--
2.34.1
>From a791f83c453e5e94d3508cde526b6d992512dc14 Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <bertranddrouvot...@gmail.com>
Date: Thu, 16 Jan 2025 15:06:01 +0000
Subject: [PATCH v8 2/3] Adding a new PgStat_WalCounters struct
This new struct contains only the counters related to the WAL statistics.
This will be used in a follow-up commit that uses the same structures but
for the PGSTAT_KIND_BACKEND statistics kind.
---
src/backend/utils/activity/pgstat_wal.c | 2 +-
src/backend/utils/adt/pgstatfuncs.c | 20 +++++++++++---------
src/include/pgstat.h | 7 ++++++-
src/tools/pgindent/typedefs.list | 1 +
4 files changed, 19 insertions(+), 11 deletions(-)
8.5% src/backend/utils/activity/
82.0% src/backend/utils/adt/
7.8% src/include/
diff --git a/src/backend/utils/activity/pgstat_wal.c b/src/backend/utils/activity/pgstat_wal.c
index 4dc41a4a590..6d024872701 100644
--- a/src/backend/utils/activity/pgstat_wal.c
+++ b/src/backend/utils/activity/pgstat_wal.c
@@ -115,7 +115,7 @@ pgstat_wal_flush_cb(bool nowait)
return true;
#define WALSTAT_ACC(fld, var_to_add) \
- (stats_shmem->stats.fld += var_to_add.fld)
+ (stats_shmem->stats.wal_counters.fld += var_to_add.fld)
WALSTAT_ACC(wal_records, wal_usage_diff);
WALSTAT_ACC(wal_fpi, wal_usage_diff);
WALSTAT_ACC(wal_bytes, wal_usage_diff);
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 620d60a0938..9de14ffd449 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -1635,10 +1635,11 @@ pg_stat_get_backend_io(PG_FUNCTION_ARGS)
* pg_stat_wal_build_tuple
*
* Helper routine for pg_stat_get_wal() returning one tuple based on the contents
- * of wal_stats.
+ * of wal_counters.
*/
static Datum
-pg_stat_wal_build_tuple(PgStat_WalStats wal_stats)
+pg_stat_wal_build_tuple(PgStat_WalCounters wal_counters,
+ TimestampTz stat_reset_timestamp)
{
#define PG_STAT_WAL_COLS 5
TupleDesc tupdesc;
@@ -1662,20 +1663,20 @@ pg_stat_wal_build_tuple(PgStat_WalStats wal_stats)
BlessTupleDesc(tupdesc);
/* Fill values and NULLs */
- values[0] = Int64GetDatum(wal_stats.wal_records);
- values[1] = Int64GetDatum(wal_stats.wal_fpi);
+ values[0] = Int64GetDatum(wal_counters.wal_records);
+ values[1] = Int64GetDatum(wal_counters.wal_fpi);
/* Convert to numeric. */
- snprintf(buf, sizeof buf, UINT64_FORMAT, wal_stats.wal_bytes);
+ snprintf(buf, sizeof buf, UINT64_FORMAT, wal_counters.wal_bytes);
values[2] = DirectFunctionCall3(numeric_in,
CStringGetDatum(buf),
ObjectIdGetDatum(0),
Int32GetDatum(-1));
- values[3] = Int64GetDatum(wal_stats.wal_buffers_full);
+ values[3] = Int64GetDatum(wal_counters.wal_buffers_full);
- if (wal_stats.stat_reset_timestamp != 0)
- values[4] = TimestampTzGetDatum(wal_stats.stat_reset_timestamp);
+ if (stat_reset_timestamp != 0)
+ values[4] = TimestampTzGetDatum(stat_reset_timestamp);
else
nulls[4] = true;
@@ -1694,7 +1695,8 @@ pg_stat_get_wal(PG_FUNCTION_ARGS)
/* Get statistics about WAL activity */
wal_stats = pgstat_fetch_stat_wal();
- return (pg_stat_wal_build_tuple(*wal_stats));
+ return (pg_stat_wal_build_tuple(wal_stats->wal_counters,
+ wal_stats->stat_reset_timestamp));
}
/*
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index fc651d03cf9..438736870b3 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -474,12 +474,17 @@ typedef struct PgStat_StatTabEntry
PgStat_Counter total_autoanalyze_time;
} PgStat_StatTabEntry;
-typedef struct PgStat_WalStats
+typedef struct PgStat_WalCounters
{
PgStat_Counter wal_records;
PgStat_Counter wal_fpi;
uint64 wal_bytes;
PgStat_Counter wal_buffers_full;
+} PgStat_WalCounters;
+
+typedef struct PgStat_WalStats
+{
+ PgStat_WalCounters wal_counters;
TimestampTz stat_reset_timestamp;
} PgStat_WalStats;
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index e3e09a2207e..19d510c9ec3 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2188,6 +2188,7 @@ PgStat_SubXactStatus
PgStat_TableCounts
PgStat_TableStatus
PgStat_TableXactStatus
+PgStat_WalCounters
PgStat_WalStats
PgXmlErrorContext
PgXmlStrictness
--
2.34.1
>From e4cebfe49be300d37ddf54dd58a44c73c642f4ba Mon Sep 17 00:00:00 2001
From: Bertrand Drouvot <bertranddrouvot...@gmail.com>
Date: Mon, 6 Jan 2025 10:00:00 +0000
Subject: [PATCH v8 3/3] per backend WAL statistics
Now that commit 9aea73fc61 added backend-level statistics to pgstats (and
per backend IO statistics) we can more easily add per backend statistics.
This commit adds per backend WAL statistics using the same layer as pg_stat_wal,
except that it is now possible to know how much WAL activity is happening in each
backend rather than an overall aggregate of all the activity. A function called
pg_stat_get_backend_wal() is added to access this data depending on the
PID of a backend.
The same limitation as in 9aea73fc61 persists, meaning that Auxiliary processes
are not included in this set of statistics.
XXX: bump catalog version
---
doc/src/sgml/monitoring.sgml | 19 ++++++
src/backend/utils/activity/pgstat_backend.c | 64 +++++++++++++++++++++
src/backend/utils/activity/pgstat_wal.c | 2 +
src/backend/utils/adt/pgstatfuncs.c | 52 ++++++++++++++++-
src/include/catalog/pg_proc.dat | 7 +++
src/include/pgstat.h | 13 +++--
src/include/utils/pgstat_internal.h | 3 +-
src/test/regress/expected/stats.out | 14 +++++
src/test/regress/sql/stats.sql | 6 ++
9 files changed, 171 insertions(+), 9 deletions(-)
14.0% doc/src/sgml/
34.5% src/backend/utils/activity/
25.9% src/backend/utils/adt/
7.7% src/include/catalog/
3.9% src/include/utils/
7.4% src/test/regress/expected/
5.6% src/test/regress/sql/
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 3dfd059b7ee..6b5c9b23c3a 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -4856,6 +4856,25 @@ description | Waiting for a newly initialized WAL file to reach durable storage
</para></entry>
</row>
+ <row>
+ <entry id="pg-stat-get-backend-wal" role="func_table_entry"><para role="func_signature">
+ <indexterm>
+ <primary>pg_stat_get_backend_wal</primary>
+ </indexterm>
+ <function>pg_stat_get_backend_wal</function> ( <type>integer</type> )
+ <returnvalue>record</returnvalue>
+ </para>
+ <para>
+ Returns WAL statistics about the backend with the specified
+ process ID. The output fields are exactly the same as the ones in the
+ <structname>pg_stat_wal</structname> view.
+ </para>
+ <para>
+ The function does not return WAL statistics for the checkpointer,
+ the background writer, the startup process and the autovacuum launcher.
+ </para></entry>
+ </row>
+
<row>
<entry role="func_table_entry"><para role="func_signature">
<indexterm>
diff --git a/src/backend/utils/activity/pgstat_backend.c b/src/backend/utils/activity/pgstat_backend.c
index 4a667e7019c..cf3fac678c2 100644
--- a/src/backend/utils/activity/pgstat_backend.c
+++ b/src/backend/utils/activity/pgstat_backend.c
@@ -35,6 +35,14 @@
*/
static PgStat_BackendPending PendingBackendStats;
+/*
+ * WAL usage counters saved from pgWalUsage at the previous call to
+ * pgstat_report_wal(). This is used to calculate how much WAL usage
+ * happens between pgstat_report_wal() calls, by subtracting
+ * the previous counters from the current ones.
+ */
+static WalUsage prevBackendWalUsage;
+
/*
* Utility routines to report I/O stats for backends, kept here to avoid
* exposing PendingBackendStats to the outside world.
@@ -131,6 +139,57 @@ pgstat_flush_backend_entry_io(PgStat_EntryRef *entry_ref)
MemSet(&PendingBackendStats.pending_io, 0, sizeof(PgStat_PendingIO));
}
+/*
+ * To determine whether WAL usage happened.
+ */
+static bool
+pgstat_backend_wal_have_pending(void)
+{
+ return pgWalUsage.wal_records != prevBackendWalUsage.wal_records;
+}
+
+/*
+ * Flush out locally pending backend WAL statistics. Locking is managed
+ * by the caller.
+ */
+static void
+pgstat_flush_backend_entry_wal(PgStat_EntryRef *entry_ref)
+{
+ PgStatShared_Backend *shbackendent;
+ PgStat_WalCounters *bktype_shstats;
+ WalUsage wal_usage_diff = {0};
+
+ /*
+ * This function can be called even if nothing at all has happened. Avoid
+ * taking lock for nothing in that case.
+ */
+ if (!pgstat_backend_wal_have_pending())
+ return;
+
+ shbackendent = (PgStatShared_Backend *) entry_ref->shared_stats;
+ bktype_shstats = &shbackendent->stats.wal_counters;
+
+ /*
+ * We don't update the WAL usage portion of the local WalStats elsewhere.
+ * Calculate how much WAL usage counters were increased by subtracting the
+ * previous counters from the current ones.
+ */
+ WalUsageAccumDiff(&wal_usage_diff, &pgWalUsage, &prevBackendWalUsage);
+
+#define WALSTAT_ACC(fld, var_to_add) \
+ (bktype_shstats->fld += var_to_add.fld)
+ WALSTAT_ACC(wal_buffers_full, wal_usage_diff);
+ WALSTAT_ACC(wal_records, wal_usage_diff);
+ WALSTAT_ACC(wal_fpi, wal_usage_diff);
+ WALSTAT_ACC(wal_bytes, wal_usage_diff);
+#undef WALSTAT_ACC
+
+ /*
+ * Save the current counters for the subsequent calculation of WAL usage.
+ */
+ prevBackendWalUsage = pgWalUsage;
+}
+
/*
* Flush out locally pending backend statistics
*
@@ -158,6 +217,9 @@ pgstat_flush_backend(bool nowait, bits32 flags)
if (flags & PGSTAT_BACKEND_FLUSH_IO)
pgstat_flush_backend_entry_io(entry_ref);
+ if (flags & PGSTAT_BACKEND_FLUSH_WAL)
+ pgstat_flush_backend_entry_wal(entry_ref);
+
pgstat_unlock_entry(entry_ref);
return false;
@@ -205,6 +267,8 @@ pgstat_create_backend(ProcNumber procnum)
pgstat_unlock_entry(entry_ref);
MemSet(&PendingBackendStats, 0, sizeof(PgStat_BackendPending));
+
+ prevBackendWalUsage = pgWalUsage;
}
/*
diff --git a/src/backend/utils/activity/pgstat_wal.c b/src/backend/utils/activity/pgstat_wal.c
index 6d024872701..f268a610fb8 100644
--- a/src/backend/utils/activity/pgstat_wal.c
+++ b/src/backend/utils/activity/pgstat_wal.c
@@ -53,6 +53,8 @@ pgstat_report_wal(bool force)
/* flush wal stats */
pgstat_flush_wal(nowait);
+ pgstat_flush_backend(nowait, PGSTAT_BACKEND_FLUSH_WAL);
+
/* flush IO stats */
pgstat_flush_io(nowait);
}
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 9de14ffd449..6676245651c 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -1634,8 +1634,8 @@ pg_stat_get_backend_io(PG_FUNCTION_ARGS)
/*
* pg_stat_wal_build_tuple
*
- * Helper routine for pg_stat_get_wal() returning one tuple based on the contents
- * of wal_counters.
+ * Helper routine for pg_stat_get_wal() and pg_stat_get_backend_wal() returning
+ * one tuple based on the contents of wal_counters.
*/
static Datum
pg_stat_wal_build_tuple(PgStat_WalCounters wal_counters,
@@ -1684,6 +1684,54 @@ pg_stat_wal_build_tuple(PgStat_WalCounters wal_counters,
PG_RETURN_DATUM(HeapTupleGetDatum(heap_form_tuple(tupdesc, values, nulls)));
}
+/*
+ * Returns WAL statistics for a backend with given PID.
+ */
+Datum
+pg_stat_get_backend_wal(PG_FUNCTION_ARGS)
+{
+ int pid;
+ PGPROC *proc;
+ ProcNumber procNumber;
+ PgStat_Backend *backend_stats;
+ PgStat_WalCounters bktype_stats;
+ PgBackendStatus *beentry;
+
+ pid = PG_GETARG_INT32(0);
+ proc = BackendPidGetProc(pid);
+
+ /*
+ * This could be an auxiliary process but these do not report backend
+ * statistics due to pgstat_tracks_backend_bktype(), so there is no need
+ * for an extra call to AuxiliaryPidGetProc().
+ */
+ if (!proc)
+ PG_RETURN_NULL();
+
+ procNumber = GetNumberFromPGProc(proc);
+
+ beentry = pgstat_get_beentry_by_proc_number(procNumber);
+ if (!beentry)
+ PG_RETURN_NULL();
+
+ backend_stats = pgstat_fetch_stat_backend(procNumber);
+ if (!backend_stats)
+ PG_RETURN_NULL();
+
+ /* if PID does not match, leave */
+ if (beentry->st_procpid != pid)
+ PG_RETURN_NULL();
+
+ /* backend may be gone, so recheck in case */
+ if (beentry->st_backendType == B_INVALID)
+ PG_RETURN_NULL();
+
+ bktype_stats = backend_stats->wal_counters;
+
+ /* save tuples with data from this PgStat_WalCounters */
+ return (pg_stat_wal_build_tuple(bktype_stats, backend_stats->stat_reset_timestamp));
+}
+
/*
* Returns statistics of WAL activity
*/
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index af9546de23d..399fccb1afb 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5954,6 +5954,13 @@
proargmodes => '{o,o,o,o,o}',
proargnames => '{wal_records,wal_fpi,wal_bytes,wal_buffers_full,stats_reset}',
prosrc => 'pg_stat_get_wal' },
+{ oid => '8037', descr => 'statistics: backend WAL activity',
+ proname => 'pg_stat_get_backend_wal', provolatile => 'v',
+ proparallel => 'r', prorettype => 'record', proargtypes => 'int4',
+ proallargtypes => '{int4,int8,int8,numeric,int8,timestamptz}',
+ proargmodes => '{i,o,o,o,o,o}',
+ proargnames => '{backend_pid,wal_records,wal_fpi,wal_bytes,wal_buffers_full,stats_reset}',
+ prosrc => 'pg_stat_get_backend_wal' },
{ oid => '6248', descr => 'statistics: information about WAL prefetching',
proname => 'pg_stat_get_recovery_prefetch', prorows => '1', proretset => 't',
provolatile => 'v', prorettype => 'record', proargtypes => '',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 438736870b3..8a706ddabab 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -340,12 +340,6 @@ typedef struct PgStat_IO
PgStat_BktypeIO stats[BACKEND_NUM_TYPES];
} PgStat_IO;
-typedef struct PgStat_Backend
-{
- TimestampTz stat_reset_timestamp;
- PgStat_BktypeIO io_stats;
-} PgStat_Backend;
-
/* ---------
* PgStat_BackendPending Non-flushed backend stats.
* ---------
@@ -488,6 +482,13 @@ typedef struct PgStat_WalStats
TimestampTz stat_reset_timestamp;
} PgStat_WalStats;
+typedef struct PgStat_Backend
+{
+ TimestampTz stat_reset_timestamp;
+ PgStat_BktypeIO io_stats;
+ PgStat_WalCounters wal_counters;
+} PgStat_Backend;
+
/*
* Functions in pgstat.c
*/
diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h
index 06dcea3f0dc..2385839d83f 100644
--- a/src/include/utils/pgstat_internal.h
+++ b/src/include/utils/pgstat_internal.h
@@ -622,7 +622,8 @@ extern void pgstat_archiver_snapshot_cb(void);
/* flags for pgstat_flush_backend() */
#define PGSTAT_BACKEND_FLUSH_IO (1 << 0) /* Flush I/O statistics */
-#define PGSTAT_BACKEND_FLUSH_ALL (PGSTAT_BACKEND_FLUSH_IO)
+#define PGSTAT_BACKEND_FLUSH_WAL (1 << 1) /* Flush WAL statistics */
+#define PGSTAT_BACKEND_FLUSH_ALL (PGSTAT_BACKEND_FLUSH_IO | PGSTAT_BACKEND_FLUSH_WAL)
extern bool pgstat_flush_backend(bool nowait, bits32 flags);
extern bool pgstat_backend_flush_cb(bool nowait);
diff --git a/src/test/regress/expected/stats.out b/src/test/regress/expected/stats.out
index 093e6368dbb..b3c303c98cb 100644
--- a/src/test/regress/expected/stats.out
+++ b/src/test/regress/expected/stats.out
@@ -832,6 +832,8 @@ SELECT sessions > :db_stat_sessions FROM pg_stat_database WHERE datname = (SELEC
SELECT num_requested AS rqst_ckpts_before FROM pg_stat_checkpointer \gset
-- Test pg_stat_wal (and make a temp table so our temp schema exists)
SELECT wal_bytes AS wal_bytes_before FROM pg_stat_wal \gset
+-- Test pg_stat_get_backend_wal (and make a temp table so our temp schema exists)
+SELECT wal_bytes AS backend_wal_bytes_before from pg_stat_get_backend_wal(pg_backend_pid()) \gset
CREATE TEMP TABLE test_stats_temp AS SELECT 17;
DROP TABLE test_stats_temp;
-- Checkpoint twice: The checkpointer reports stats after reporting completion
@@ -851,6 +853,18 @@ SELECT wal_bytes > :wal_bytes_before FROM pg_stat_wal;
t
(1 row)
+SELECT pg_stat_force_next_flush();
+ pg_stat_force_next_flush
+--------------------------
+
+(1 row)
+
+SELECT wal_bytes > :backend_wal_bytes_before FROM pg_stat_get_backend_wal(pg_backend_pid());
+ ?column?
+----------
+ t
+(1 row)
+
-- Test pg_stat_get_backend_idset() and some allied functions.
-- In particular, verify that their notion of backend ID matches
-- our temp schema index.
diff --git a/src/test/regress/sql/stats.sql b/src/test/regress/sql/stats.sql
index 0a44e14d9f4..ad3f7b7e66a 100644
--- a/src/test/regress/sql/stats.sql
+++ b/src/test/regress/sql/stats.sql
@@ -423,6 +423,9 @@ SELECT num_requested AS rqst_ckpts_before FROM pg_stat_checkpointer \gset
-- Test pg_stat_wal (and make a temp table so our temp schema exists)
SELECT wal_bytes AS wal_bytes_before FROM pg_stat_wal \gset
+-- Test pg_stat_get_backend_wal (and make a temp table so our temp schema exists)
+SELECT wal_bytes AS backend_wal_bytes_before from pg_stat_get_backend_wal(pg_backend_pid()) \gset
+
CREATE TEMP TABLE test_stats_temp AS SELECT 17;
DROP TABLE test_stats_temp;
@@ -435,6 +438,9 @@ CHECKPOINT;
SELECT num_requested > :rqst_ckpts_before FROM pg_stat_checkpointer;
SELECT wal_bytes > :wal_bytes_before FROM pg_stat_wal;
+SELECT pg_stat_force_next_flush();
+SELECT wal_bytes > :backend_wal_bytes_before FROM pg_stat_get_backend_wal(pg_backend_pid());
+
-- Test pg_stat_get_backend_idset() and some allied functions.
-- In particular, verify that their notion of backend ID matches
-- our temp schema index.
--
2.34.1
