Re: Show WAL write and fsync stats in pg_stat_io

On Fri, Jan 31, 2025 at 11:29:31AM +0300, Nazir Bilal Yavuz wrote:
> On Wed, 29 Jan 2025 at 18:16, Bertrand Drouvot
> <bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
>> I think that's the main reason why ff99918c625 added this new GUC (looking at
>> the commit message). I'd feel more comfortable if we keep it.
>
> As Michael suggested, I will run a couple of benchmarks to see the
> actual effect of this change. Then let's see if this affects anything.

I've looked at bit at all that today, and something like the attached
is what seems like the best streamlined version to me for the main
feature. I am also planning to run some short benchmarks with
track_io_timing=on on HEAD and with the patch, then see the
difference, without any relationship to track_wal_io_timing.

The comment additions in pgstat_count_io_op_time() were worth a patch
of their own. This part has been applied as b998fedab74c, after a few
tweaks of my own.
--
Michael