Skip to content

Commit 559efce

Browse files
MasaoFujiiMasaoFujii
committed
Add num_done counter to the pg_stat_checkpointer view.
Checkpoints can be skipped when the server is idle. The existing num_timed and num_requested counters in pg_stat_checkpointer track both completed and skipped checkpoints, but there was no way to count only the completed ones. This commit introduces the num_done counter, which tracks only completed checkpoints, making it easier to see how many were actually performed. Bump catalog version. Author: Anton A. Melnikov Reviewed-by: Fujii Masao Discussion: https://postgr.es/m/9ea77f40-818d-4841-9dee-158ac8f6e690@oss.nttdata.com
1 parent 20cfec8 commit 559efce

File tree

11 files changed

+60
-19
lines changed

11 files changed

+60
-19
lines changed

‎doc/src/sgml/monitoring.sgml

Lines changed: 10 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -3063,7 +3063,16 @@ description | Waiting for a newly initialized WAL file to reach durable storage
30633063
<structfield>num_requested</structfield> <type>bigint</type>
30643064
</para>
30653065
<para>
3066-
Number of requested checkpoints that have been performed
3066+
Number of backend requested checkpoints
3067+
</para></entry>
3068+
</row>
3069+
3070+
<row>
3071+
<entry role="catalog_table_entry"><para role="column_definition">
3072+
<structfield>num_done</structfield> <type>bigint</type>
3073+
</para>
3074+
<para>
3075+
Number of checkpoints that have been performed
30673076
</para></entry>
30683077
</row>
30693078

‎src/backend/access/transam/xlog.c

Lines changed: 7 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -6878,8 +6878,11 @@ update_checkpoint_display(int flags, bool restartpoint, bool reset)
68786878
* In this case, we only insert an XLOG_CHECKPOINT_SHUTDOWN record, and it's
68796879
* both the record marking the completion of the checkpoint and the location
68806880
* from which WAL replay would begin if needed.
6881+
*
6882+
* Returns true if a new checkpoint was performed, or false if it was skipped
6883+
* because the system was idle.
68816884
*/
6882-
void
6885+
bool
68836886
CreateCheckPoint(int flags)
68846887
{
68856888
bool shutdown;
@@ -6971,7 +6974,7 @@ CreateCheckPoint(int flags)
69716974
END_CRIT_SECTION();
69726975
ereport(DEBUG1,
69736976
(errmsg_internal("checkpoint skipped because system is idle")));
6974-
return;
6977+
return false;
69756978
}
69766979
}
69776980

@@ -7353,6 +7356,8 @@ CreateCheckPoint(int flags)
73537356
CheckpointStats.ckpt_segs_added,
73547357
CheckpointStats.ckpt_segs_removed,
73557358
CheckpointStats.ckpt_segs_recycled);
7359+
7360+
return true;
73567361
}
73577362

73587363
/*

‎src/backend/catalog/system_views.sql

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1138,6 +1138,7 @@ CREATE VIEW pg_stat_checkpointer AS
11381138
SELECT
11391139
pg_stat_get_checkpointer_num_timed() AS num_timed,
11401140
pg_stat_get_checkpointer_num_requested() AS num_requested,
1141+
pg_stat_get_checkpointer_num_performed() AS num_done,
11411142
pg_stat_get_checkpointer_restartpoints_timed() AS restartpoints_timed,
11421143
pg_stat_get_checkpointer_restartpoints_requested() AS restartpoints_req,
11431144
pg_stat_get_checkpointer_restartpoints_performed() AS restartpoints_done,

‎src/backend/postmaster/checkpointer.c

Lines changed: 25 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -460,10 +460,7 @@ CheckpointerMain(char *startup_data, size_t startup_data_len)
460460
* Do the checkpoint.
461461
*/
462462
if (!do_restartpoint)
463-
{
464-
CreateCheckPoint(flags);
465-
ckpt_performed = true;
466-
}
463+
ckpt_performed = CreateCheckPoint(flags);
467464
else
468465
ckpt_performed = CreateRestartPoint(flags);
469466

@@ -484,7 +481,7 @@ CheckpointerMain(char *startup_data, size_t startup_data_len)
484481

485482
ConditionVariableBroadcast(&CheckpointerShmem->done_cv);
486483

487-
if (ckpt_performed)
484+
if (!do_restartpoint)
488485
{
489486
/*
490487
* Note we record the checkpoint start time not end time as
@@ -493,18 +490,32 @@ CheckpointerMain(char *startup_data, size_t startup_data_len)
493490
*/
494491
last_checkpoint_time = now;
495492

496-
if (do_restartpoint)
497-
PendingCheckpointerStats.restartpoints_performed++;
493+
if (ckpt_performed)
494+
PendingCheckpointerStats.num_performed++;
498495
}
499496
else
500497
{
501-
/*
502-
* We were not able to perform the restartpoint (checkpoints
503-
* throw an ERROR in case of error). Most likely because we
504-
* have not received any new checkpoint WAL records since the
505-
* last restartpoint. Try again in 15 s.
506-
*/
507-
last_checkpoint_time = now - CheckPointTimeout + 15;
498+
if (ckpt_performed)
499+
{
500+
/*
501+
* The same as for checkpoint. Please see the
502+
* corresponding comment.
503+
*/
504+
last_checkpoint_time = now;
505+
506+
PendingCheckpointerStats.restartpoints_performed++;
507+
}
508+
else
509+
{
510+
/*
511+
* We were not able to perform the restartpoint
512+
* (checkpoints throw an ERROR in case of error). Most
513+
* likely because we have not received any new checkpoint
514+
* WAL records since the last restartpoint. Try again in
515+
* 15 s.
516+
*/
517+
last_checkpoint_time = now - CheckPointTimeout + 15;
518+
}
508519
}
509520

510521
ckpt_active = false;

‎src/backend/utils/activity/pgstat_checkpointer.c

Lines changed: 2 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -49,6 +49,7 @@ pgstat_report_checkpointer(void)
4949
#define CHECKPOINTER_ACC(fld) stats_shmem->stats.fld += PendingCheckpointerStats.fld
5050
CHECKPOINTER_ACC(num_timed);
5151
CHECKPOINTER_ACC(num_requested);
52+
CHECKPOINTER_ACC(num_performed);
5253
CHECKPOINTER_ACC(restartpoints_timed);
5354
CHECKPOINTER_ACC(restartpoints_requested);
5455
CHECKPOINTER_ACC(restartpoints_performed);
@@ -127,6 +128,7 @@ pgstat_checkpointer_snapshot_cb(void)
127128
#define CHECKPOINTER_COMP(fld) pgStatLocal.snapshot.checkpointer.fld -= reset.fld;
128129
CHECKPOINTER_COMP(num_timed);
129130
CHECKPOINTER_COMP(num_requested);
131+
CHECKPOINTER_COMP(num_performed);
130132
CHECKPOINTER_COMP(restartpoints_timed);
131133
CHECKPOINTER_COMP(restartpoints_requested);
132134
CHECKPOINTER_COMP(restartpoints_performed);

‎src/backend/utils/adt/pgstatfuncs.c

Lines changed: 6 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1191,6 +1191,12 @@ pg_stat_get_checkpointer_num_requested(PG_FUNCTION_ARGS)
11911191
PG_RETURN_INT64(pgstat_fetch_stat_checkpointer()->num_requested);
11921192
}
11931193

1194+
Datum
1195+
pg_stat_get_checkpointer_num_performed(PG_FUNCTION_ARGS)
1196+
{
1197+
PG_RETURN_INT64(pgstat_fetch_stat_checkpointer()->num_performed);
1198+
}
1199+
11941200
Datum
11951201
pg_stat_get_checkpointer_restartpoints_timed(PG_FUNCTION_ARGS)
11961202
{

‎src/include/access/xlog.h

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -239,7 +239,7 @@ extern void LocalProcessControlFile(bool reset);
239239
extern WalLevel GetActiveWalLevelOnStandby(void);
240240
extern void StartupXLOG(void);
241241
extern void ShutdownXLOG(int code, Datum arg);
242-
extern void CreateCheckPoint(int flags);
242+
extern bool CreateCheckPoint(int flags);
243243
extern bool CreateRestartPoint(int flags);
244244
extern WALAvailability GetWALAvailability(XLogRecPtr targetLSN);
245245
extern void XLogPutNextOid(Oid nextOid);

‎src/include/catalog/catversion.h

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -57,6 +57,6 @@
5757
*/
5858

5959
/* yyyymmddN */
60-
#define CATALOG_VERSION_NO 202409271
60+
#define CATALOG_VERSION_NO 202409301
6161

6262
#endif

‎src/include/catalog/pg_proc.dat

Lines changed: 5 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -5820,6 +5820,11 @@
58205820
proname => 'pg_stat_get_checkpointer_num_requested', provolatile => 's',
58215821
proparallel => 'r', prorettype => 'int8', proargtypes => '',
58225822
prosrc => 'pg_stat_get_checkpointer_num_requested' },
5823+
{ oid => '8599',
5824+
descr => 'statistics: number of checkpoints performed by the checkpointer',
5825+
proname => 'pg_stat_get_checkpointer_num_performed', provolatile => 's',
5826+
proparallel => 'r', prorettype => 'int8', proargtypes => '',
5827+
prosrc => 'pg_stat_get_checkpointer_num_performed' },
58235828
{ oid => '6327',
58245829
descr => 'statistics: number of timed restartpoints started by the checkpointer',
58255830
proname => 'pg_stat_get_checkpointer_restartpoints_timed', provolatile => 's',

‎src/include/pgstat.h

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -294,6 +294,7 @@ typedef struct PgStat_CheckpointerStats
294294
{
295295
PgStat_Counter num_timed;
296296
PgStat_Counter num_requested;
297+
PgStat_Counter num_performed;
297298
PgStat_Counter restartpoints_timed;
298299
PgStat_Counter restartpoints_requested;
299300
PgStat_Counter restartpoints_performed;

‎src/test/regress/expected/rules.out

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1824,6 +1824,7 @@ pg_stat_bgwriter| SELECT pg_stat_get_bgwriter_buf_written_clean() AS buffers_cle
18241824
pg_stat_get_bgwriter_stat_reset_time() AS stats_reset;
18251825
pg_stat_checkpointer| SELECT pg_stat_get_checkpointer_num_timed() AS num_timed,
18261826
pg_stat_get_checkpointer_num_requested() AS num_requested,
1827+
pg_stat_get_checkpointer_num_performed() AS num_done,
18271828
pg_stat_get_checkpointer_restartpoints_timed() AS restartpoints_timed,
18281829
pg_stat_get_checkpointer_restartpoints_requested() AS restartpoints_req,
18291830
pg_stat_get_checkpointer_restartpoints_performed() AS restartpoints_done,

0 commit comments

Comments
 (0)
pFad - Phonifier reborn

Pfad - The Proxy pFad of © 2024 Garber Painting. All rights reserved.

Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.


Alternative Proxies:

Alternative Proxy

pFad Proxy

pFad v3 Proxy

pFad v4 Proxy