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From: Fujii Masao <masao.fujii@gmail.com>
Date: Thu, 9 Jul 2026 09:57:27 +0900
Message-ID: 
 <CAHGQGwH8n4BMjBJcL1ob6YTJYn1kTmVwO6mEYoEGyrGyNXaaXw@mail.gmail.com>
Subject: Re: pgsql: Refactor how some aux processes advertise their ProcNumber
To: Thom Brown <thom@linux.com>
Cc: Heikki Linnakangas <heikki.linnakangas@iki.fi>,
 pgsql-committers@lists.postgresql.org
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On Thu, Jul 9, 2026 at 6:57=E2=80=AFAM Thom Brown <thom@linux.com> wrote:
> @@ -724,6 +725,14 @@ InitAuxiliaryProcess(void)
>      */
>     PGSemaphoreReset(MyProc->sem);
>
> +   /* Some aux processes are also advertised in ProcGlobal */
> +   if (MyBackendType =3D=3D B_AUTOVAC_LAUNCHER)
> +       pg_atomic_write_u32(&ProcGlobal->avLauncherProc, MyProcNumber);
>
> I'm looking for the places this gets called from. I can only see
> auxprocess.c which the launcher doesn't go through. The same question
> for similar code in AuxiliaryProcKill().

You're right. The autovacuum launcher does not go through
AuxiliaryProcessMainCommon(), so it never calls
InitAuxiliaryProcess(). Instead, it initializes its PGPROC with
InitProcess().

As a result, the avLauncherProc assignment added to
InitAuxiliaryProcess() is never executed for the launcher, and the
corresponding cleanup in AuxiliaryProcKill() is never reached either.

It seems we should move the avLauncherProc set/clear operations to
InitProcess()/ProcKill() path, as in the attached patch.

Regards,

--=20
Fujii Masao

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