Re: Fix 035_standby_logical_decoding.pl race conditions

On Wed, Apr 9, 2025 at 11:24 AM Bertrand Drouvot
<bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
>
> On Wed, Apr 09, 2025 at 12:03:06PM +0900, Michael Paquier wrote:
> > On Tue, Apr 08, 2025 at 06:42:53AM +0000, Bertrand Drouvot wrote:
> > > Fully agree. Will need to find another way to prevent a process to wait between the
> > > wakeup and the detach. I'll open a dedicated thread.
> >
> > By the way, there is a small thing that's itching me a bit about the
> > change done in LogStandbySnapshot() for 105b2cb33617. Could it be
> > useful for debugging to add a elog(DEBUG1) with the LSN returned by
> > GetInsertRecPtr() when taking the short path? We don't have any
> > visibility when the shortcut path is taken, which seems annoying in
> > the long term if we use the injection point skip-log-running-xacts for
> > other tests, and I suspect that there will be some as the standby
> > snapshots can be really annoying in tests where we want a predictible
> > set of WAL records when wal_level is "replica" or "logical".
>
> Yeah, I also think that would be good to have some way to debug this.
>

I can't think of a good reason to have this DEBUG1 as there is no
predictability of it getting generated even with tests using an
injection point. OTOH, I don't have any objections to it if you would
like to proceed with this.

--
With Regards,
Amit Kapila.