Re: Add wait event for CommitDelay

On Fri, 5 Dec 2025 at 17:15, Sami Imseih <samimseih(at)gmail(dot)com> wrote:

> Hi,
>
> > So, my colleague Ants Aasma found that a wait_event is missing for
> CommitDelay.
> > This just looks like it was missed, please enlighten if it is left out
> intentionally.
>
> I do not know if it was left out intentionally, there are no comments on
> that
> matter.
>
> I am not sure how widely used this GUC is, but from the quick test that I
> did using pgench TPC-B workload with 50 clients, it seems useful
> since a DBA can set commit_delay too high and you will easily observe
> a single backend constantly in this delay which will impact tps.
> It's good to show this clearly as a wait event.
>
> As far as the patch goes, It makes sense to put this under
> "WaitEventTimeout",
> but it should be placed after CHECKPOINT_WRITE_DELAY in
> alphabetical order, and the description could be improved a bit.
> How about? "Waiting for the commit delay before WAL flush."
>
> Thanks for the review of the patch. Please find the attachment for the
updated version.

--
Regards,
Rafia Sabih
CYBERTEC PostgreSQL International GmbH