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In-Reply-To: 
 <CAExHW5sYaeZqzjUrG2V9U5ZFnZHW+X-Q2Zb9L62CRbeuAwC4EA@mail.gmail.com>
From: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Date: Sun, 5 Apr 2026 21:53:43 +0530
Message-ID: 
 <CAExHW5uoKOZKmmCb=4azZ5Lx0uT+CrmievXdSweAYHbo9HXMnQ@mail.gmail.com>
Subject: Re: Better shared data structure management and resizable shared data
 structures
To: Heikki Linnakangas <hlinnaka@iki.fi>
Cc: Matthias van de Meent <boekewurm+postgres@gmail.com>,
 Robert Haas <robertmhaas@gmail.com>,
	Andres Freund <andres@anarazel.de>,
 pgsql-hackers <pgsql-hackers@postgresql.org>,
	chaturvedipalak1911@gmail.com
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 <https://www.postgresql.org/message-id/CAExHW5uoKOZKmmCb%3D4azZ5Lx0uT%2BCrmievXdSweAYHbo9HXMnQ%40mail.gmail.com>
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On Sun, Apr 5, 2026 at 7:38=E2=80=AFPM Ashutosh Bapat
<ashutosh.bapat.oss@gmail.com> wrote:
>
> On Sun, Apr 5, 2026 at 11:18=E2=80=AFAM Ashutosh Bapat
> <ashutosh.bapat.oss@gmail.com> wrote:
> >
> >
> > I will post my resizable shmem structures patch in a separate email in
> > this thread but continue to review your patches.
>
> I reviewed the SLRU patch. This is the first time I am looking at SLRU
> code, so my review may not be sufficient. As far as I understand, the
> patch faithfully copies the functionality from the old system to the
> new system. I didn't find any issues there.
>
> I think calls to SimpleLruRequest() reads much better than SimpleLruInit(=
).
>
> Both MultiXactShmemInit and MultiXactShmemAttach set
> OldestMemberMXactId, OldestVisibleMXactId. In future if we add another
> global variable to point to the shared memory, somebody needs to
> remember to initialize it in both these functions. Maybe deduplicate
> it with something like attached? Similarly for PredicateLock related
> changes.

Sorry, I attached the wrong patch. Here's the right patch.

--=20
Best Wishes,
Ashutosh Bapat

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