Re: [PATCH] Prevent repeated deadlock-check signals in standby buffer pin waits

Thanks for the review.
v2 attached, with the suggested initialization added for symmetry.

Agreed this is an improvement rather than a bug fix,
so I've updated the CF tag to Performance accordingly.

I also verified the fix locally on a primary-standby setup,
using the buffer-pin conflict scenario from src/test/recovery/t/
031_recovery_conflict.pl
(aborted INSERT + cursor on standby + VACUUM FREEZE on primary).
On master, strace showed 9 SIGUSR1 broadcasts to the conflicting backend
over a 10-second window (one per deadlock_timeout).
With the patch applied, only 1 broadcast over the same window.

Patch attached.

--
JoongHyuk Shin

On Tue, Apr 21, 2026 at 2:55 PM Michael Paquier <michael(at)paquier(dot)xyz> wrote:

> On Tue, Apr 21, 2026 at 02:42:38PM +0900, Fujii Masao wrote:
> > Since this change improves recovery-conflict behavior rather than fixing
> a bug,
> > it doesn't seem to need backpatching and we may need to wait until v20
> > development opens (probably July) before committing it.
>
> Yeah, this one is an improvement, not an actual bug, so let's wait for
> v20 if worth doing (I did not check it).
> --
> Michael
>