Feedback-ID: i0fe9450f:Fastmail
Date: Tue, 17 Mar 2026 08:37:39 +0900
From: Michael Paquier <michael@paquier.xyz>
To: "Aya Iwata (Fujitsu)" <iwata.aya@fujitsu.com>
Cc: Peter Smith <smithpb2250@gmail.com>,
	Pavel Stehule <pavel.stehule@gmail.com>,
	Chao Li <li.evan.chao@gmail.com>,
	"Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>,
	pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: [PROPOSAL] Termination of Background Workers for ALTER/DROP
 DATABASE
Message-ID: <abiUQ5MBGG9MDM1h@paquier.xyz>
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On Mon, Mar 16, 2026 at 04:23:40PM +0900, Michael Paquier wrote:
> Aye, we have a timing issue here, and at first it seemed to me that
> this was a bug in the backend logic.  But actually I suspect that it
> is simpler than that: we don't disable autovacuum so couldn't an
> autovacuum worker connect to the database "testdb" that we are trying
> to rename in this query?  I cannot be 100% sure because we have
> reduced the log activity for the sake of the tests, but that feels
> possible to me.  We could try to disable autovacuum entirely, then see
> if the situation gets better in the buildfarm.
>=20
> The failure rate is so low that it is likely going to take a few weeks
> to check the stability of the situation.  We could also lot more
> things, of course, as a temporary solution.

After sleeping on it, I do not have a better idea than the attached,
so we could always get that into the tree and see if the situation
improves, even if it would take time.  Iwata-san and others, what do
you think?  Perhaps you could think of a different reason causing this
failure?
--
Michael

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diff --git a/src/test/modules/worker_spi/t/002_worker_terminate.pl b/src/te=
st/modules/worker_spi/t/002_worker_terminate.pl
index 6d3794355981..21dfb5961289 100644
--- a/src/test/modules/worker_spi/t/002_worker_terminate.pl
+++ b/src/test/modules/worker_spi/t/002_worker_terminate.pl
@@ -59,6 +59,10 @@ sub run_bgworker_interruptible_test
=20
 my $node =3D PostgreSQL::Test::Cluster->new('mynode');
 $node->init;
+$node->append_conf(
+	"postgresql.conf", qq(
+autovacuum =3D off
+));
 $node->start;
=20
 # Check if the extension injection_points is available, as it may be

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