Re: BUG #18988: DROP SUBSCRIPTION locks not-yet-accessed database

On Fri, 15 Aug 2025 at 11:58, Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
>
> On Fri, Aug 15, 2025 at 11:52 AM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> >
> > On Thu, Aug 14, 2025 at 5:04 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> > >
> > > On Thu, Aug 14, 2025 at 4:32 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> > > >
> > > > On Thu, Aug 14, 2025 at 2:18 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> > > > >
> > > > > On Thu, Aug 14, 2025 at 2:05 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> > > > > >
> > > > > > Yeah this looks fine to me. PFA patches for back branches.
> > > > > >
> > > > >
> > > > > Can we add a test based on the scenario reported in this email?
> > > >
> > > > At first, I thought we can just add this test in subscription.sql, but
> > > > IMHO we should not do that because after testing DROP SUBSCRIPTION
> > > > give error we should eventually DROP the subscription for cleanup by
> > > > creating the slot and enabling the subscription (as shown below[1])
> > > > but I that realized during regression wal_level is not logical so we
> > > > are not allowed to create the logical slot. So maybe we should write
> > > > it in 100_bugs.pl? Am I missing something?
> > > >
> > >
> > > Another alternative is for cleanup instead of creating a missing slot
> > > we can just set the slot_name=NONE and then drop. I will move ahead
> > > with this approach.
> > >
> >
> > Yeah, that sounds good to me.
> >
>
> PFA, updated patches for v13 to head, make check-world is passing for
> all the branches for v15+ we had upgrade test which also run
> regression test so we additionally have to set max_wal_senders=1 for
> 002_pg_upgrade.pl

This change will run not just the newly added test, but the entire
regression suite under the new configuration. Should we consider
moving this test elsewhere such as into the 100_bugs:
diff --git a/src/bin/pg_upgrade/t/002_pg_upgrade.pl
b/src/bin/pg_upgrade/t/002_pg_upgrade.pl
index 4b5e895809b..284b2ef07e0 100644
--- a/src/bin/pg_upgrade/t/002_pg_upgrade.pl
+++ b/src/bin/pg_upgrade/t/002_pg_upgrade.pl
@@ -225,6 +225,8 @@ $oldnode->init(%old_node_params);
# Override log_statement=all set by Cluster.pm. This avoids large amounts
# of log traffic that slow this test down even more when run under valgrind.
$oldnode->append_conf('postgresql.conf', 'log_statement = none');
+$oldnode->append_conf('postgresql.conf', 'wal_level = replica');
+$oldnode->append_conf('postgresql.conf', 'max_wal_senders = 1');

Regards,
Vignesh