MIME-Version: 1.0
References: <aPBsd2e2SqLs0Kdk@paquier.xyz> <CAFj8pRB_FH-Pcth9XFcpY2OTasVOP-2DfYOsVxL38igw0O4hdg@mail.gmail.com>
 <OS7PR01MB119647141272DBF9364A1C5AAEAADA@OS7PR01MB11964.jpnprd01.prod.outlook.com>
 <CAFj8pRCRnN4SyZDPbQwTyKZ_kVHfwLG6udCXsXDTG_z9fWwYQg@mail.gmail.com>
 <OS7PR01MB119648203BD748ED008FA5BF5EAABA@OS7PR01MB11964.jpnprd01.prod.outlook.com>
 <CAFj8pRCn0=jn4yaeg1JoxxxnUNeXm1KCouES8Puq_GgBsXrNTQ@mail.gmail.com>
 <OS7PR01MB1196405302B700736580DEE49EAA8A@OS7PR01MB11964.jpnprd01.prod.outlook.com>
 <CAFj8pRBk7zTKoxAAKAihNQuimztniWHPyRWHKp2iHq_2hH+dvQ@mail.gmail.com>
 <OS7PR01MB11964C83E8E543743581250B0EAB3A@OS7PR01MB11964.jpnprd01.prod.outlook.com>
 <CAHut+PvP6H2soK05c_0JZC8--=h4nWEtxYE_nJGjRkQr=25F1w@mail.gmail.com>
 <aVs3IpiYjmq3gLEn@paquier.xyz> <CAHut+PtSVYKU4vfaRev4FMdbeZ3ukvxRy4X7uK05jv_9WMYafA@mail.gmail.com>
 <OS7PR01MB1196426354C0294148A06AC65EA86A@OS7PR01MB11964.jpnprd01.prod.outlook.com>
In-Reply-To: <OS7PR01MB1196426354C0294148A06AC65EA86A@OS7PR01MB11964.jpnprd01.prod.outlook.com>
From: Peter Smith <smithpb2250@gmail.com>
Date: Tue, 6 Jan 2026 08:18:39 +1100
Message-ID: <CAHut+PtZh+B_-z_TzmToUhL4-sBrf7dfH0uAb7VU-jkXFmHQSA@mail.gmail.com>
Subject: Re: [PROPOSAL] Termination of Background Workers for ALTER/DROP DATABASE
To: "Aya Iwata (Fujitsu)" <iwata.aya@fujitsu.com>
Cc: Michael Paquier <michael@paquier.xyz>, 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>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Archived-At: <https://www.postgresql.org/message-id/CAHut%2BPtZh%2BB_-z_TzmToUhL4-sBrf7dfH0uAb7VU-jkXFmHQSA%40mail.gmail.com>
Precedence: bulk

On Tue, Jan 6, 2026 at 2:06=E2=80=AFAM Aya Iwata (Fujitsu)
<iwata.aya@fujitsu.com> wrote:
>
> Hi
>
> Thank you for your comments and suggestions on the previous version patch=
es!
> I believe this feature become much better.
>
> I've created a v13 patch incorporating Peter-san's suggestions.
>

Some review comments for v13-0001.

=3D=3D=3D=3D=3D=3D
src/backend/storage/ipc/procarray.c

CountOtherDBBackends:

1.
  * If there are other backends in the DB, we will wait a maximum of 5 seco=
nds
- * for them to exit.  Autovacuum backends are encouraged to exit early by
- * sending them SIGTERM, but normal user backends are just waited for.
+ * for them to exit.  Autovacuum backends and background workers are encou=
raged
+ * to exit early by sending them PMSIGNAL_BACKGROUND_WORKER_CHANGE, but no=
rmal
+ * user backends are just waited for.

This did not seem like the correct fix for my previous review comment
[1, comment #3], because the autovacuum backends are still killed with
SIGTERM, right?

=3D=3D=3D=3D=3D=3D
.../worker_spi/t/002_worker_terminate.pl

2.
+# Confirm that the non-interruptible bgworker is still running.
+my $result =3D $node->safe_psql(
+ "postgres", qq(
+        SELECT count(1) FROM pg_stat_activity
+ WHERE backend_type =3D 'worker_spi dynamic';));

The indentation of the "SELECT" still does not look correct to me. Did
you run pgperltidy on this file?

=3D=3D=3D=3D=3D=3D
[1] https://www.postgresql.org/message-id/CAHut%2BPtSVYKU4vfaRev4FMdbeZ3ukv=
xRy4X7uK05jv_9WMYafA%40mail.gmail.com

Kind Regards,
Peter Smith.
Fujitsu Australia