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Date: Mon, 1 Sep 2025 11:03:55 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Noah Misch <noah@leadboat.com>, Andres Freund <andres@anarazel.de>,
	pgsql-hackers@postgresql.org,
	Melanie Plageman <melanieplageman@gmail.com>,
	Thomas Munro <thomas.munro@gmail.com>,
	Heikki Linnakangas <hlinnaka@iki.fi>
Subject: Re: Buffer locking is special (hints, checksums, AIO writes)
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On Wed, Aug 27, 2025 at 10:03:08AM -0400, Robert Haas wrote:
> If we were to use the existing PostgreSQL naming convention, I think
> I'd probably argue that the nearest parallel to this level is
> ShareUpdateExclusive: a self-exclusive lock level that permits
> ordinary table access to continue while blocking exclusive locks, used
> for an in-flight maintenance operation. But that's arguable, of
> course.

ShareUpdateExclusive is a term that's been used for some time now and
relates to knowledge that's quite spread in the tree, so it feels like
a natural fit for the use-case described on this thread as we'd want a
self-conflicting lock.  share-exclusive did not sound that bad to me,
TBH, quite the contrary, when applied to buffer locking for aio.

"intent" is also a word I've bumped quite a lot into while looking at
some naming convention, but this is more related to the fact that a
lock is going to be taken, which we don't really have.  So that feels
off.
--
Michael

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