Re: Show WAL write and fsync stats in pg_stat_io

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>

To: Michael Paquier <michael@paquier.xyz>

Cc: Nazir Bilal Yavuz <byavuz81@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, "bharath.rupireddyforpostgres@gmail.com" <bharath.rupireddyforpostgres@gmail.com>

Date: 2023-11-07T23:30:48Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Fix copy-paste error related to the autovacuum launcher in pgstat_io.c
- 17d8bba6dad1 18.0 landed
Move SQL tests of pg_stat_io for WAL data to recovery test 029_stats_restart
- 428fadb7e97e 18.0 landed
Add data for WAL in pg_stat_io and backend statistics
- a051e71e28a1 18.0 landed
Improve comment on top of pgstat_count_io_op_time()
- b998fedab74c 18.0 landed
Refactor pgstat_prepare_io_time() with an input argument instead of a GUC
- 3c9d9acae0bc 17.0 landed

Hi,

On 2023-10-26 15:28:32 +0900, Michael Paquier wrote:
> On top of that pg_stat_io is now for block-based I/O operations, so
> that does not fit entirely in the picture, though I guess that Melanie
> has thought more on the matter than me.  That may be also a matter of
> taste.

I strongly disagree. A significant part of the design of pg_stat_io was to
make it possible to collect multiple sources of IO in a single view, so that
sysadmins don't have to look in dozens of places to figure out what is causing
what kind of IO.

We should over time collect all sources of IO in pg_stat_io. For some things
we might want to also have more detailed information in other views (e.g. it
doesn't make sense to track FPIs in pg_stat_io, but does make sense in
pg_stat_wal) - but that should be in addition, not instead of.

Greetings,

Andres Freund