From: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>
To: 'Michael Paquier' <michael@paquier.xyz>
CC: "'pgsql-hackers@lists.postgresql.org'"
	<pgsql-hackers@lists.postgresql.org>
Subject: RE: ReplicationSlotRelease() crashes when the instance is in the
 single user mode
Thread-Topic: ReplicationSlotRelease() crashes when the instance is in the
 single user mode
Thread-Index: AduBxJdn64KPa5CETf+apI8CWWnvvAAB/XMAAAIqX/AAASMfAAAAQnZg
Date: Tue, 18 Feb 2025 08:23:43 +0000
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Precedence: bulk

Dear Michael,

> Ah, good point for the slot drop.  So 0ce5cf2ef24f is claiming that
> some of these manipulations are OK.  I didn't suspect this one.

Yeah, I think so.

> Slot advancing is a very different beast, unfortunately, that may
> depend on many other subsystems.  For example with logical slots we
> would finish by calling rm_decode, which could be outside of core.
> Justifying that this operation is supported in single-user mode is
> larger than what you are suggesting here..

OK. Actually, I do not have any use-cases in my mind. I played because
I found a special path for single user mode in ReplicationSlotAcquire()
so that I wanted to see the behavior.

Best regards,
Hayato Kuroda
FUJITSU LIMITED