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From: Nathan Bossart <nathandbossart@gmail.com>
To: Sami Imseih <samimseih@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>
Cc: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Cc: Rahila Syed <rahilasyed90@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: Improve LWLock tranche name visibility across backends
Date: Mon, 25 Aug 2025 16:44:55 -0500
Message-ID: <aKzZV8Acib6pFesE@nathan> (raw)
In-Reply-To: <CAA5RZ0vh7jrGDwJgkKtw-LR5fBH-tRNpGJnPivdKedtqJ7HGCQ@mail.gmail.com>
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On Mon, Aug 25, 2025 at 04:37:21PM -0500, Sami Imseih wrote:
> When we lookup from shared array only, we need to take a shared lock
> every lookup. Acquiring that lock is what I am trying to avoid. You
> are saying it's not worth optimizing that part, correct?

Why do we need a shared lock here?  IIUC there's no chance that existing
entries will change.  We'll only ever add new ones to the end.

-- 
nathan





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