Re: per backend WAL statistics - Mailing list pgsql-hackers

From Michael Paquier
Subject Re: per backend WAL statistics
Date
Msg-id Z7_V23z5O87Wyf1R@paquier.xyz
Whole thread Raw
In response to Re: per backend WAL statistics  (Bertrand Drouvot <bertranddrouvot.pg@gmail.com>)
Responses Re: per backend WAL statistics
List pgsql-hackers
On Wed, Feb 26, 2025 at 10:59:11AM +0000, Bertrand Drouvot wrote:
> Yup. That's what we've done in pg_stat_io_build_tuples() too (ff7c40d7fd6).
> Without this we'd get "2000-01-01 00:00:00+00" in the stats_reset field of
> pg_stat_get_backend_wal() and pg_stat_get_backend_io().

Right, forgot about this part.

> That was not needed for pg_stat_io and pg_stat_wal because the stats_reset field
> was already non null after initdb.

0001 was OK, so done.

In 0002, couldn't it be better to have the pg_stat_get_backend_stats()
static in pgstatfuncs.c?  In 0003, pg_stat_get_backend_wal() is also
in pgstatfuncs.c, meaning that all the callers of
pg_stat_get_backend_stats() would be in this file.

-typedef struct PgStat_Backend
-{
-    TimestampTz stat_reset_timestamp;
-    PgStat_BktypeIO io_stats;
-} PgStat_Backend;
-
 /* ---------
  * PgStat_BackendPending    Non-flushed backend stats.
  * ---------

In 0003, let's keep PgStat_BackendPending grouped with PgStat_Backend,
so it sounds better to move both of them after the WAL stats
structures.
--
Michael

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