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From: Robert Haas <robertmhaas@gmail.com>
Date: Wed, 27 Aug 2025 15:22:55 -0400
Message-ID: 
 <CA+TgmoY0hnGMqyzoM8SBiJVUT=+n0KyWrmXVVEmR-itD-c3uSQ@mail.gmail.com>
Subject: Re: Buffer locking is special (hints, checksums, AIO writes)
To: Andres Freund <andres@anarazel.de>
Cc: Noah Misch <noah@leadboat.com>, pgsql-hackers@postgresql.org,
	Melanie Plageman <melanieplageman@gmail.com>,
 Thomas Munro <thomas.munro@gmail.com>,
	Heikki Linnakangas <hlinnaka@iki.fi>
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On Wed, Aug 27, 2025 at 12:18=E2=80=AFPM Andres Freund <andres@anarazel.de>=
 wrote:
> Which would leave us with:
> - reference (pins today)
> - share
> - share-exclusive
> - exclusive
> - cleanup
>
> This doesn't quite seem to map onto the heavyweight lock levels in a sens=
ible
> way...

Could do: ACCESS SHARE, SHARE, SHARE UPDATE EXCLUSIVE, EXCLUSIVE,
ACCESS EXCLUSIVE.

I've always thought that a pin was a lot like an access share lock and
a cleanup lock was a lot like an access exclusive lock.

But then again, using the same terminology for two different things
might be confusing.

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