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From: Robert Haas <robertmhaas@gmail.com>
Date: Tue, 25 Nov 2025 19:13:03 -0500
Message-ID: 
 <CA+TgmoaSpDa8dqWBwjRAittp+XTKN698Tpg3CEMpi=08sKc4Sw@mail.gmail.com>
Subject: Re: pgsql: Teach DSM registry to ERROR if attaching to an
 uninitialized ent
To: Nathan Bossart <nathandbossart@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Tue, Nov 25, 2025 at 4:16=E2=80=AFPM Nathan Bossart <nathandbossart@gmai=
l.com> wrote:
> My tests seem happy, so I will plan on committing these patches tomorrow.
> The only difference in v4 is that pg_get_dsm_registry_allocations() will =
no
> longer show partially-initialized entries.  I thought that was the best
> option in this case because such entries shouldn't have any allocated
> memory, and retrying GetNamed*() would set *found to false.

Without actually opening the new patch files, that seems OK to me. I
think the important thing about such a view is that it shouldn't make
any state changes; it should just show how things are. In my ideal
world, it would probably show partially-initialized entires in some
distinguishable way, like with a null size. But leaving them out is
also defensible. The thing that I think really matters for failure
cases is the ability to retry whatever's gone wrong, either to get it
fixed or to see the error, and the other changes already accomplish
that goal, so I'm happy.

--=20
Robert Haas
EDB: http://www.enterprisedb.com