Re: synchronized_standby_slots behavior inconsistent with quorum-based synchronous replication

Hi Shveta,

On Wed, Apr 1, 2026 at 12:06 PM shveta malik <shveta(dot)malik(at)gmail(dot)com> wrote:
>
> On Thu, Mar 26, 2026 at 5:23 PM Ashutosh Sharma <ashu(dot)coek88(at)gmail(dot)com> wrote:
> >
> >
> > PFA patch addressing all the comments above and let me know for any
> > further comments.
> >
>
> Thank You Ashutosh. Doc looks good to me. Few comments:
>
> 3)
> What is the execution time for this new test?
> I ran it on my VM (which is slightly on the slower side), and the
> runtime varies between ~60 seconds and ~140 seconds. I executed it
> around 10–15 times. Most runs completed in about 65 seconds (which is
> still more), but a few were significantly longer (100+ seconds).
> During the longer runs, I noticed the following entry in pub.log
> (possibly related to Test Scenario E taking more time?). Could you
> please try running this on your end as well?
>
> 2026-03-31 19:45:45.557 IST client backend[145705]
> 053_synchronized_standby_slots_quorum.pl LOG: statement: SELECT
> active_pid IS NOT NULL
> AND restart_lsn IS NOT NULL
> AND restart_lsn < '0/03000450'::pg_lsn
> FROM pg_replication_slots
> WHERE slot_name = 'sb1_slot';
>
> Just for reference, the complete failover test
> (t/040_standby_failover_slots_sync.pl) takes somewhere between 7 to
> 10sec on my VM.
>

My concern with this new test is that it's both slow to run and prone
to flakiness, which makes me question whether it's worth keeping.

--
With Regards,
Ashutosh Sharma.