Hey,
Le mer. 2 oct. 2024 à 11:12, Benoit Lobréau <benoit.lobr...@dalibo.com> a
écrit :
> Hi,
>
> Thanks for your imput ! I will fix the doc as proposed and do the split
> as soon as I have time.
>
>
I've done the split, but I didn't go any further than that.
Two patches attached:
* v5-0001 adds the metrics (same patch than v3-0001 for pg_stat_statements)
* v5-0002 handles the metrics for pg_stat_database.
"make check" works, and I also did a few other tests without any issues.
Regards.
--
Guillaume.
From 9413829616bdc0806970647c15d7d6bbd96489d1 Mon Sep 17 00:00:00 2001
From: Guillaume Lelarge <guillaume.lela...@dalibo.com>
Date: Mon, 7 Oct 2024 08:45:36 +0200
Subject: [PATCH v5 1/2] Introduce two new counters in EState
They will be used by two other patchs to populate new columns in
pg_stat_database and pg_statements.
---
src/backend/executor/execUtils.c | 3 +++
src/backend/executor/nodeGather.c | 3 +++
src/backend/executor/nodeGatherMerge.c | 3 +++
src/include/nodes/execnodes.h | 3 +++
4 files changed, 12 insertions(+)
diff --git a/src/backend/executor/execUtils.c b/src/backend/executor/execUtils.c
index 5737f9f4eb..1908481999 100644
--- a/src/backend/executor/execUtils.c
+++ b/src/backend/executor/execUtils.c
@@ -162,6 +162,9 @@ CreateExecutorState(void)
estate->es_jit_flags = 0;
estate->es_jit = NULL;
+ estate->es_parallelized_workers_launched = 0;
+ estate->es_parallelized_workers_planned = 0;
+
/*
* Return the executor state structure
*/
diff --git a/src/backend/executor/nodeGather.c b/src/backend/executor/nodeGather.c
index 5d4ffe989c..0fb915175a 100644
--- a/src/backend/executor/nodeGather.c
+++ b/src/backend/executor/nodeGather.c
@@ -182,6 +182,9 @@ ExecGather(PlanState *pstate)
/* We save # workers launched for the benefit of EXPLAIN */
node->nworkers_launched = pcxt->nworkers_launched;
+ estate->es_parallelized_workers_launched += pcxt->nworkers_launched;
+ estate->es_parallelized_workers_planned += pcxt->nworkers_to_launch;
+
/* Set up tuple queue readers to read the results. */
if (pcxt->nworkers_launched > 0)
{
diff --git a/src/backend/executor/nodeGatherMerge.c b/src/backend/executor/nodeGatherMerge.c
index 45f6017c29..149ab23d90 100644
--- a/src/backend/executor/nodeGatherMerge.c
+++ b/src/backend/executor/nodeGatherMerge.c
@@ -223,6 +223,9 @@ ExecGatherMerge(PlanState *pstate)
/* We save # workers launched for the benefit of EXPLAIN */
node->nworkers_launched = pcxt->nworkers_launched;
+ estate->es_parallelized_workers_launched += pcxt->nworkers_launched;
+ estate->es_parallelized_workers_planned += pcxt->nworkers_to_launch;
+
/* Set up tuple queue readers to read the results. */
if (pcxt->nworkers_launched > 0)
{
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index aab59d681c..f898590ece 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -708,6 +708,9 @@ typedef struct EState
bool es_use_parallel_mode; /* can we use parallel workers? */
+ int es_parallelized_workers_launched;
+ int es_parallelized_workers_planned;
+
/* The per-query shared memory area to use for parallel execution. */
struct dsa_area *es_query_dsa;
--
2.46.2
From 873c03b99e1ccc05bac4c71b5f070e0dbe0bd779 Mon Sep 17 00:00:00 2001
From: benoit <benoit.lobr...@dalibo.com>
Date: Mon, 7 Oct 2024 10:12:46 +0200
Subject: [PATCH v5 2/2] Adds four parallel workers stat columns to
pg_stat_database
* parallel_workers_planned
* parallel_workers_launched
* parallel_maint_workers_planned
* parallel_maint_workers_launched
---
doc/src/sgml/monitoring.sgml | 36 +++++++++++++++++++
src/backend/access/brin/brin.c | 4 +++
src/backend/access/nbtree/nbtsort.c | 4 +++
src/backend/catalog/system_views.sql | 4 +++
src/backend/commands/vacuumparallel.c | 5 +++
src/backend/executor/execMain.c | 7 ++++
src/backend/utils/activity/pgstat_database.c | 36 +++++++++++++++++++
src/backend/utils/adt/pgstatfuncs.c | 12 +++++++
src/include/catalog/pg_proc.dat | 20 +++++++++++
src/include/pgstat.h | 7 ++++
src/test/regress/expected/rules.out | 4 +++
src/test/regress/expected/select_parallel.out | 11 ++++++
src/test/regress/expected/vacuum_parallel.out | 19 ++++++++++
src/test/regress/sql/select_parallel.sql | 8 +++++
src/test/regress/sql/vacuum_parallel.sql | 11 ++++++
15 files changed, 188 insertions(+)
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 331315f8d3..9567ca5bd1 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -3611,6 +3611,42 @@ description | Waiting for a newly initialized WAL file to reach durable storage
</para></entry>
</row>
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>parallel_workers_planned</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Number of parallel workers planned by queries on this database
+ </para></entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>parallel_workers_launched</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Number of parallel workers obtained by queries on this database
+ </para></entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>parallel_maint_workers_planned</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Number of parallel workers planned by utilities on this database
+ </para></entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>parallel_maint_workers_launched</structfield> <type>bigint</type>
+ </para>
+ <para>
+ Number of parallel workers obtained by utilities on this database
+ </para></entry>
+ </row>
+
<row>
<entry role="catalog_table_entry"><para role="column_definition">
<structfield>stats_reset</structfield> <type>timestamp with time zone</type>
diff --git a/src/backend/access/brin/brin.c b/src/backend/access/brin/brin.c
index c0b978119a..4e83091d2c 100644
--- a/src/backend/access/brin/brin.c
+++ b/src/backend/access/brin/brin.c
@@ -2544,6 +2544,10 @@ _brin_end_parallel(BrinLeader *brinleader, BrinBuildState *state)
/* Shutdown worker processes */
WaitForParallelWorkersToFinish(brinleader->pcxt);
+ pgstat_update_parallel_maint_workers_stats(
+ (PgStat_Counter) brinleader->pcxt->nworkers_to_launch,
+ (PgStat_Counter) brinleader->pcxt->nworkers_launched);
+
/*
* Next, accumulate WAL usage. (This must wait for the workers to finish,
* or we might get incomplete data.)
diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c
index 5cca0d4f52..8ee5fcf6d3 100644
--- a/src/backend/access/nbtree/nbtsort.c
+++ b/src/backend/access/nbtree/nbtsort.c
@@ -1615,6 +1615,10 @@ _bt_end_parallel(BTLeader *btleader)
/* Shutdown worker processes */
WaitForParallelWorkersToFinish(btleader->pcxt);
+ pgstat_update_parallel_maint_workers_stats(
+ (PgStat_Counter) btleader->pcxt->nworkers_to_launch,
+ (PgStat_Counter) btleader->pcxt->nworkers_launched);
+
/*
* Next, accumulate WAL usage. (This must wait for the workers to finish,
* or we might get incomplete data.)
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 3456b821bc..7e693a5bae 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -1073,6 +1073,10 @@ CREATE VIEW pg_stat_database AS
pg_stat_get_db_sessions_abandoned(D.oid) AS sessions_abandoned,
pg_stat_get_db_sessions_fatal(D.oid) AS sessions_fatal,
pg_stat_get_db_sessions_killed(D.oid) AS sessions_killed,
+ pg_stat_get_db_parallel_workers_planned(D.oid) as parallel_workers_planned,
+ pg_stat_get_db_parallel_workers_launched(D.oid) as parallel_workers_launched,
+ pg_stat_get_db_parallel_maint_workers_planned(D.oid) as parallel_maint_workers_planned,
+ pg_stat_get_db_parallel_maint_workers_launched(D.oid) as parallel_maint_workers_launched,
pg_stat_get_db_stat_reset_time(D.oid) AS stats_reset
FROM (
SELECT 0 AS oid, NULL::name AS datname
diff --git a/src/backend/commands/vacuumparallel.c b/src/backend/commands/vacuumparallel.c
index 4fd6574e12..c6f43419aa 100644
--- a/src/backend/commands/vacuumparallel.c
+++ b/src/backend/commands/vacuumparallel.c
@@ -739,6 +739,11 @@ parallel_vacuum_process_all_indexes(ParallelVacuumState *pvs, int num_index_scan
for (int i = 0; i < pvs->pcxt->nworkers_launched; i++)
InstrAccumParallelQuery(&pvs->buffer_usage[i], &pvs->wal_usage[i]);
+
+ pgstat_update_parallel_maint_workers_stats(
+ (PgStat_Counter) pvs->pcxt->nworkers_to_launch,
+ (PgStat_Counter) pvs->pcxt->nworkers_launched
+ );
}
/*
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index cc9a594cba..e749cdaa17 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -52,6 +52,7 @@
#include "miscadmin.h"
#include "nodes/queryjumble.h"
#include "parser/parse_relation.h"
+#include "pgstat.h"
#include "rewrite/rewriteHandler.h"
#include "tcop/utility.h"
#include "utils/acl.h"
@@ -483,6 +484,12 @@ standard_ExecutorEnd(QueryDesc *queryDesc)
Assert(estate != NULL);
+ if (estate->es_parallelized_workers_planned > 0) {
+ pgstat_update_parallel_workers_stats(
+ (PgStat_Counter) estate->es_parallelized_workers_planned,
+ (PgStat_Counter) estate->es_parallelized_workers_launched);
+ }
+
/*
* Check that ExecutorFinish was called, unless in EXPLAIN-only mode. This
* Assert is needed because ExecutorFinish is new as of 9.1, and callers
diff --git a/src/backend/utils/activity/pgstat_database.c b/src/backend/utils/activity/pgstat_database.c
index 29bc090974..9e72c286b2 100644
--- a/src/backend/utils/activity/pgstat_database.c
+++ b/src/backend/utils/activity/pgstat_database.c
@@ -262,6 +262,38 @@ AtEOXact_PgStat_Database(bool isCommit, bool parallel)
}
}
+/*
+ * reports parallel_workers_planned and parallel_workers_launched into
+ * PgStat_StatDBEntry
+ */
+void
+pgstat_update_parallel_workers_stats(PgStat_Counter parallel_workers_planned, PgStat_Counter parallel_workers_launched)
+{
+ PgStat_StatDBEntry *dbentry;
+ if (!OidIsValid(MyDatabaseId))
+ return;
+
+ dbentry = pgstat_prep_database_pending(MyDatabaseId);
+ dbentry->parallel_workers_planned += parallel_workers_planned;
+ dbentry->parallel_workers_launched += parallel_workers_launched;
+}
+
+/*
+ * reports parallel_maint_workers_planned and parallel_maint_workers_launched into
+ * PgStat_StatDBEntry
+ */
+void
+pgstat_update_parallel_maint_workers_stats(PgStat_Counter parallel_maint_workers_planned, PgStat_Counter parallel_maint_workers_launched)
+{
+ PgStat_StatDBEntry *dbentry;
+ if (!OidIsValid(MyDatabaseId))
+ return;
+
+ dbentry = pgstat_prep_database_pending(MyDatabaseId);
+ dbentry->parallel_maint_workers_planned += parallel_maint_workers_planned;
+ dbentry->parallel_maint_workers_launched += parallel_maint_workers_launched;
+}
+
/*
* Subroutine for pgstat_report_stat(): Handle xact commit/rollback and I/O
* timings.
@@ -425,6 +457,10 @@ pgstat_database_flush_cb(PgStat_EntryRef *entry_ref, bool nowait)
PGSTAT_ACCUM_DBCOUNT(sessions_abandoned);
PGSTAT_ACCUM_DBCOUNT(sessions_fatal);
PGSTAT_ACCUM_DBCOUNT(sessions_killed);
+ PGSTAT_ACCUM_DBCOUNT(parallel_workers_planned);
+ PGSTAT_ACCUM_DBCOUNT(parallel_workers_launched);
+ PGSTAT_ACCUM_DBCOUNT(parallel_maint_workers_planned);
+ PGSTAT_ACCUM_DBCOUNT(parallel_maint_workers_launched);
#undef PGSTAT_ACCUM_DBCOUNT
pgstat_unlock_entry(entry_ref);
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index f7b50e0b5a..2db4d2bb6b 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -1039,6 +1039,18 @@ PG_STAT_GET_DBENTRY_INT64(sessions_fatal)
/* pg_stat_get_db_sessions_killed */
PG_STAT_GET_DBENTRY_INT64(sessions_killed)
+/* pg_stat_get_db_parallel_workers_planned*/
+PG_STAT_GET_DBENTRY_INT64(parallel_workers_planned)
+
+/* pg_stat_get_db_parallel_workers_launched*/
+PG_STAT_GET_DBENTRY_INT64(parallel_workers_launched)
+
+/* pg_stat_get_db_parallel_maint_workers_planned*/
+PG_STAT_GET_DBENTRY_INT64(parallel_maint_workers_planned)
+
+/* pg_stat_get_db_parallel_maint_workers_launched*/
+PG_STAT_GET_DBENTRY_INT64(parallel_maint_workers_launched)
+
/* pg_stat_get_db_temp_bytes */
PG_STAT_GET_DBENTRY_INT64(temp_bytes)
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 77f54a79e6..47dc0f87eb 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5803,6 +5803,26 @@
proname => 'pg_stat_get_db_sessions_killed', provolatile => 's',
proparallel => 'r', prorettype => 'int8', proargtypes => 'oid',
prosrc => 'pg_stat_get_db_sessions_killed' },
+{ oid => '8403',
+ descr => 'statistics: number of parallel workers planned for queries',
+ proname => 'pg_stat_get_db_parallel_workers_planned', provolatile => 's',
+ proparallel => 'r', prorettype => 'int8', proargtypes => 'oid',
+ prosrc => 'pg_stat_get_db_parallel_workers_planned' },
+{ oid => '8404',
+ descr => 'statistics: number of parallel workers effectively launched for queries',
+ proname => 'pg_stat_get_db_parallel_workers_launched', provolatile => 's',
+ proparallel => 'r', prorettype => 'int8', proargtypes => 'oid',
+ prosrc => 'pg_stat_get_db_parallel_workers_launched' },
+{ oid => '8405',
+ descr => 'statistics: number of parallel workers planned for utilities',
+ proname => 'pg_stat_get_db_parallel_maint_workers_planned', provolatile => 's',
+ proparallel => 'r', prorettype => 'int8', proargtypes => 'oid',
+ prosrc => 'pg_stat_get_db_parallel_maint_workers_planned' },
+{ oid => '8406',
+ descr => 'statistics: number of parallel workers effectively launched for utilities',
+ proname => 'pg_stat_get_db_parallel_maint_workers_launched', provolatile => 's',
+ proparallel => 'r', prorettype => 'int8', proargtypes => 'oid',
+ prosrc => 'pg_stat_get_db_parallel_maint_workers_launched' },
{ oid => '3195', descr => 'statistics: information about WAL archiver',
proname => 'pg_stat_get_archiver', proisstrict => 'f', provolatile => 's',
proparallel => 'r', prorettype => 'record', proargtypes => '',
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index df53fa2d4f..1a5c489bbd 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -387,6 +387,11 @@ typedef struct PgStat_StatDBEntry
PgStat_Counter sessions_fatal;
PgStat_Counter sessions_killed;
+ PgStat_Counter parallel_workers_planned;
+ PgStat_Counter parallel_workers_launched;
+ PgStat_Counter parallel_maint_workers_planned;
+ PgStat_Counter parallel_maint_workers_launched;
+
TimestampTz stat_reset_timestamp;
} PgStat_StatDBEntry;
@@ -583,6 +588,8 @@ extern void pgstat_report_deadlock(void);
extern void pgstat_report_checksum_failures_in_db(Oid dboid, int failurecount);
extern void pgstat_report_checksum_failure(void);
extern void pgstat_report_connect(Oid dboid);
+extern void pgstat_update_parallel_workers_stats(PgStat_Counter parallel_workers_planned, PgStat_Counter parallel_workers_launched);
+extern void pgstat_update_parallel_maint_workers_stats(PgStat_Counter parallel_maint_workers_planned, PgStat_Counter parallel_maint_workers_launched);
#define pgstat_count_buffer_read_time(n) \
(pgStatBlockReadTime += (n))
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 2b47013f11..c795fb68c1 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1863,6 +1863,10 @@ pg_stat_database| SELECT oid AS datid,
pg_stat_get_db_sessions_abandoned(oid) AS sessions_abandoned,
pg_stat_get_db_sessions_fatal(oid) AS sessions_fatal,
pg_stat_get_db_sessions_killed(oid) AS sessions_killed,
+ pg_stat_get_db_parallel_workers_planned(oid) AS parallel_workers_planned,
+ pg_stat_get_db_parallel_workers_launched(oid) AS parallel_workers_launched,
+ pg_stat_get_db_parallel_maint_workers_planned(oid) AS parallel_maint_workers_planned,
+ pg_stat_get_db_parallel_maint_workers_launched(oid) AS parallel_maint_workers_launched,
pg_stat_get_db_stat_reset_time(oid) AS stats_reset
FROM ( SELECT 0 AS oid,
NULL::name AS datname
diff --git a/src/test/regress/expected/select_parallel.out b/src/test/regress/expected/select_parallel.out
index 2c63aa85a6..db3ca8b198 100644
--- a/src/test/regress/expected/select_parallel.out
+++ b/src/test/regress/expected/select_parallel.out
@@ -1,6 +1,17 @@
--
-- PARALLEL
--
+-- Get a reference for parallel stats in pg_stat_database
+select pg_stat_force_next_flush();
+ pg_stat_force_next_flush
+--------------------------
+
+(1 row)
+
+select parallel_workers_planned as parallel_workers_planned_before,
+ parallel_workers_launched as parallel_workers_launched_before
+from pg_stat_database
+where datname = 'regression' \gset
create function sp_parallel_restricted(int) returns int as
$$begin return $1; end$$ language plpgsql parallel restricted;
begin;
diff --git a/src/test/regress/expected/vacuum_parallel.out b/src/test/regress/expected/vacuum_parallel.out
index ddf0ee544b..4c9c5cb1fd 100644
--- a/src/test/regress/expected/vacuum_parallel.out
+++ b/src/test/regress/expected/vacuum_parallel.out
@@ -37,9 +37,28 @@ WHERE oid in ('regular_sized_index'::regclass, 'typically_sized_index'::regclass
2
(1 row)
+-- Get a reference for parallel stats in pg_stat_database
+SELECT sum(parallel_maint_workers_planned) AS parallel_maint_workers_planned_before,
+ sum(parallel_maint_workers_launched) AS parallel_maint_workers_launched_before
+FROM pg_stat_database \gset
-- Parallel VACUUM with B-Tree page deletions, ambulkdelete calls:
DELETE FROM parallel_vacuum_table;
VACUUM (PARALLEL 4, INDEX_CLEANUP ON) parallel_vacuum_table;
+-- Check parallel stats in pg_stat_database
+SELECT pg_stat_force_next_flush();
+ pg_stat_force_next_flush
+--------------------------
+
+(1 row)
+
+SELECT sum(parallel_maint_workers_planned) > :'parallel_maint_workers_planned_before' AS maint_wrk_planned,
+ sum(parallel_maint_workers_launched) > :'parallel_maint_workers_launched_before' AS maint_wrk_launched
+FROM pg_stat_database;
+ maint_wrk_planned | maint_wrk_launched
+-------------------+--------------------
+ t | t
+(1 row)
+
-- Since vacuum_in_leader_small_index uses deduplication, we expect an
-- assertion failure with bug #17245 (in the absence of bugfix):
INSERT INTO parallel_vacuum_table SELECT i FROM generate_series(1, 10000) i;
diff --git a/src/test/regress/sql/select_parallel.sql b/src/test/regress/sql/select_parallel.sql
index 9ba1328fd2..2ff0f7f21c 100644
--- a/src/test/regress/sql/select_parallel.sql
+++ b/src/test/regress/sql/select_parallel.sql
@@ -2,6 +2,14 @@
-- PARALLEL
--
+-- Get a reference for parallel stats in pg_stat_database
+select pg_stat_force_next_flush();
+select parallel_workers_planned as parallel_workers_planned_before,
+ parallel_workers_launched as parallel_workers_launched_before
+from pg_stat_database
+where datname = 'regression' \gset
+
+
create function sp_parallel_restricted(int) returns int as
$$begin return $1; end$$ language plpgsql parallel restricted;
diff --git a/src/test/regress/sql/vacuum_parallel.sql b/src/test/regress/sql/vacuum_parallel.sql
index 1d23f33e39..d0d7851e6a 100644
--- a/src/test/regress/sql/vacuum_parallel.sql
+++ b/src/test/regress/sql/vacuum_parallel.sql
@@ -31,10 +31,21 @@ WHERE oid in ('regular_sized_index'::regclass, 'typically_sized_index'::regclass
pg_relation_size(oid) >=
pg_size_bytes(current_setting('min_parallel_index_scan_size'));
+-- Get a reference for parallel stats in pg_stat_database
+SELECT sum(parallel_maint_workers_planned) AS parallel_maint_workers_planned_before,
+ sum(parallel_maint_workers_launched) AS parallel_maint_workers_launched_before
+FROM pg_stat_database \gset
+
-- Parallel VACUUM with B-Tree page deletions, ambulkdelete calls:
DELETE FROM parallel_vacuum_table;
VACUUM (PARALLEL 4, INDEX_CLEANUP ON) parallel_vacuum_table;
+-- Check parallel stats in pg_stat_database
+SELECT pg_stat_force_next_flush();
+SELECT sum(parallel_maint_workers_planned) > :'parallel_maint_workers_planned_before' AS maint_wrk_planned,
+ sum(parallel_maint_workers_launched) > :'parallel_maint_workers_launched_before' AS maint_wrk_launched
+FROM pg_stat_database;
+
-- Since vacuum_in_leader_small_index uses deduplication, we expect an
-- assertion failure with bug #17245 (in the absence of bugfix):
INSERT INTO parallel_vacuum_table SELECT i FROM generate_series(1, 10000) i;
--
2.46.2
