database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2026-10-23 13:29:09 +03:00
Code Activity

Restrict pg_stat_io entries for data checksum processes

Browse Source 
The data checksums launcher and workers were exposed in pg_stat_io
with the same broad set of object/context combinations as general
background workers. However, several of those entries can never
accumulate I/O statistics for these processes, such as bulkwrite,
relation init, temporary relation, and launcher vacuum entries.

Teach pgstat_tracks_io_object() and pgstat_tracks_io_op() about the
actual I/O performed by the data checksum processes. Keep the entries
needed for catalog scans, including bulkread catalog scans, worker
relation processing with a vacuum access strategy, and WAL writes and
initialization, while excluding WAL reads and other object/context
combinations that can never be used.

Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAHGQGwHz_-nt+YkHDMRZNBZrnoHro8cMOgSwuXEmSYT6vxgQ=w@mail.gmail.com
Backpatch-through: 19
This commit is contained in:
Fujii Masao
2026-07-17 20:16:34 +09:00
parent 2572fc5312
commit 3aa54433b0
2 changed files with 34 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
src/backend/utils/activity/pgstat_io.c
View File

@@ -464,6 +464,37 @@ pgstat_tracks_io_object(BackendType bktype, IOObject io_object,
io_context == IOCONTEXT_BULKWRITE)
return false;
/*
* The data checksums launcher scans catalogs and emits WAL records for
* checksum state changes. Catalog scans can use a bulkread strategy.
*/
if (bktype == B_DATACHECKSUMSWORKER_LAUNCHER)
{
if (io_object == IOOBJECT_WAL ||
(io_object == IOOBJECT_RELATION &&
(io_context == IOCONTEXT_BULKREAD ||
io_context == IOCONTEXT_NORMAL)))
return true;
return false;
}
/*
* The worker also scans catalogs, then processes relations using a vacuum
* access strategy. Catalog scans can use a bulkread strategy.
*/
if (bktype == B_DATACHECKSUMSWORKER_WORKER)
{
if (io_object == IOOBJECT_WAL ||
(io_object == IOOBJECT_RELATION &&
(io_context == IOCONTEXT_BULKREAD ||
io_context == IOCONTEXT_NORMAL ||
io_context == IOCONTEXT_VACUUM)))
return true;
return false;
}
return true;
}
@@ -507,6 +538,8 @@ pgstat_tracks_io_op(BackendType bktype, IOObject io_object,
if (io_object == IOOBJECT_WAL && io_op == IOOP_READ &&
(bktype == B_WAL_RECEIVER || bktype == B_BG_WRITER ||
bktype == B_AUTOVAC_LAUNCHER || bktype == B_AUTOVAC_WORKER ||
bktype == B_DATACHECKSUMSWORKER_LAUNCHER ||
bktype == B_DATACHECKSUMSWORKER_WORKER ||
bktype == B_WAL_WRITER))
return false;

9
src/test/regress/expected/stats.out
View File

@@ -52,19 +52,12 @@ client backend|temp relation|normal
client backend|wal|init
client backend|wal|normal
datachecksums launcher|relation|bulkread
datachecksums launcher|relation|bulkwrite
datachecksums launcher|relation|init
datachecksums launcher|relation|normal
datachecksums launcher|relation|vacuum
datachecksums launcher|temp relation|normal
datachecksums launcher|wal|init
datachecksums launcher|wal|normal
datachecksums worker|relation|bulkread
datachecksums worker|relation|bulkwrite
datachecksums worker|relation|init
datachecksums worker|relation|normal
datachecksums worker|relation|vacuum
datachecksums worker|temp relation|normal
datachecksums worker|wal|init
datachecksums worker|wal|normal
io worker|relation|bulkread
@@ -111,7 +104,7 @@ walsummarizer|wal|init
walsummarizer|wal|normal
walwriter|wal|init
walwriter|wal|normal
(95 rows)
(88 rows)
\a
-- ensure that both seqscan and indexscan plans are allowed
SET enable_seqscan TO on;