From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dominique Devienne <ddevienne@gmail.com>
cc: Ron Johnson <ronljohnsonjr@gmail.com>,
        "pgsql-generallists.postgresql.org" <pgsql-general@lists.postgresql.org>
Subject: Re: Option on `postgres` CLI to shutdown when there are no more active connections?
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Comments: In-reply-to Dominique Devienne <ddevienne@gmail.com>
	message dated "Mon, 13 Oct 2025 17:15:20 +0200"
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Date: Mon, 13 Oct 2025 11:37:09 -0400
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Dominique Devienne <ddevienne@gmail.com> writes:
> On Mon, Oct 13, 2025 at 5:08=E2=80=AFPM Ron Johnson <ronljohnsonjr@gmail=
.com> wrote:
>> Shared memory means that I can stomp all over you, and you can't stop m=
e.  That's the antithesis of ACID.

> SHM is how SQLite in WAL mode coordinates access to the same DB from
> several connections. So if it's good enough for SQLite, I don't see
> what it would be wrong for PostgreSQL too.

SQLite has accepted the cost that comes with being embedded, which is
that application-side memory-stomping bugs can destroy the database.
Postgres is not willing to make that tradeoff.  From a pure
developer's perspective, every time we got a bug report we'd have to
ask "did you observe this while running embedded?" and then demand a
repro that uses a non-embedded database.  We are not going to help
application authors debug their own bugs, especially not when we have
no visibility into what those are.

> SQLite is also ACID.

I guess they have a different set of assumptions about what that
buzzword means.

			regards, tom lane