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From: Melanie Plageman <melanieplageman@gmail.com>
Date: Mon, 24 Nov 2025 16:04:41 -0500
Message-ID: 
 <CAAKRu_Z9BzF=mHeiy+tUJ524_c7q0sBabschMX83Shag2XohpA@mail.gmail.com>
Subject: Re: Buffer locking is special (hints, checksums, AIO writes)
To: Andres Freund <andres@anarazel.de>
Cc: Matthias van de Meent <boekewurm+postgres@gmail.com>,
 pgsql-hackers@postgresql.org,
	Thomas Munro <thomas.munro@gmail.com>, Heikki Linnakangas <hlinnaka@iki.fi>,
 Noah Misch <noah@leadboat.com>,
	Robert Haas <robertmhaas@gmail.com>,
 Michael Paquier <michael.paquier@gmail.com>
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On Mon, Nov 24, 2025 at 3:58=E2=80=AFPM Andres Freund <andres@anarazel.de> =
wrote:
>
> Hi,
>
> On 2025-11-19 21:47:49 -0500, Andres Freund wrote:
> > 0001: A straight-up bugfix in lwlock.c - albeit for a bug that seems cu=
rrently
> >       effectively harmless.
>
> Does anybody have opinions about whether to backpatch this fix? Given tha=
t it
> has no real consequences I'm mildly inclined not to, but maybe there are =
cases
> where the additional wait list lock cycle matters?

Since it is a mistake, I am mildly in favor of backporting to avoid
confusion for future developers. It's pretty weird that LWLockWakeup()
has to be called again to actually unset LW_FLAG_HAS_WAITERS. But
since it's not really harmful, this is a very mild opinion.

- Melanie