Date: Wed, 27 Aug 2025 16:04:51 -0700
From: Noah Misch <noah@leadboat.com>
To: Andres Freund <andres@anarazel.de>
Cc: Robert Haas <robertmhaas@gmail.com>, 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)
Message-ID: <20250827230451.a4.nmisch@google.com>
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On Wed, Aug 27, 2025 at 03:29:02PM -0400, Andres Freund wrote:
> On 2025-08-27 12:14:41 -0700, Noah Misch wrote:
> > On Wed, Aug 27, 2025 at 12:18:27PM -0400, Andres Freund wrote:
> > > > On Tue, Aug 26, 2025 at 05:00:13PM -0400, Andres Freund wrote:
> > > > > On 2025-08-26 16:21:36 -0400, Robert Haas wrote:
> > > > > > On Fri, Aug 22, 2025 at 3:45 PM Andres Freund <andres@anarazel.de> wrote:
> > > > > > > DOES ANYBODY HAVE A BETTER NAME THAN SHARE-EXCLUSIVE???!?

> > > Which would leave us with:
> > > - reference (pins today)
> > > - share
> > > - share-exclusive
> > > - exclusive
> > > - cleanup

> > Compared to share-exclusive, I think I'd prefer a name that describes the use
> > cases, "set-hints-or-write" (or separate "write" and "set-hints" levels).

Another name idea is "self-exclusive", to contrast with "exclusive" excluding
all of (exclusive, self-exclusive, share).

Fortunately, not much code will acquire this lock type.  Hence, there's
relatively little damage if the name is less obvious than older lock types or
if the name changes later.