Re: Fwd: [BUG]: the walsender does not update its IO statistics until it exits

On Thu, 3 Apr 2025 at 12:54, Bertrand Drouvot
<bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
>
> Hi,
>
> On Thu, Apr 03, 2025 at 09:25:02AM +0530, vignesh C wrote:
> > On Mon, 31 Mar 2025 at 18:35, Bertrand Drouvot
> > <bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
> > >
> > Couple of suggestions:
>
> Thanks for looking at it!
>
> > 1) I felt we can include a similar verification for one of the logical
> > replication tests too:
> > +# Wait for the walsender to update its IO statistics.
> >
> > +# Has to be done before the next restart and far enough from the
> > +# pg_stat_reset_shared('io') to minimize the risk of polling for too long.
> > +$node_primary->poll_query_until(
> > + 'postgres',
> > + qq[SELECT sum(reads) > 0
> > + FROM pg_catalog.pg_stat_io
> > + WHERE backend_type = 'walsender'
> > + AND object = 'wal']
> > + )
> > + or die
> > + "Timed out while waiting for the walsender to update its IO statistics";
> > +
>
> Initially ([1]) it was added in 035_standby_logical_decoding.pl. But this
> test (035) is already racy enough that I felt better to move it to 001_stream_rep.pl
> (see [2]) instead.
>
> I don't think that's a big issue as the code path being changed in the patch is
> shared between logical and physical walsenders. That said that would not hurt to
> add a logical walsender test, but I would prefer it to be outside
> 035_standby_logical_decoding.pl. Do you have a suggestion for the location of
> such a test?

Can we add it to one of the subscription tests, such as 001_rep_changes.pl?

Regards,
Vignesh