Date: Mon, 25 Aug 2025 14:02:26 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Sami Imseih <samimseih@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: GetNamedLWLockTranche crashes on Windows in normal backend
Message-ID: <aKyzQuljgqo7-YIs@nathan>
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On Mon, Aug 25, 2025 at 01:44:22PM -0500, Sami Imseih wrote:
> Another approach is to just change GetNamedLWLockTranche to use
> NamedLWLockTrancheArray since that is already copied in EXEC_BACKEND, and
> allow GetNamedLWLockTranche to continue to be used outside of startup. In
> this case, we will need to add num_lwlocks field to
> NamedLWLockTrancheArray. This might be better to backpatch, since we will
> not be changing user facing behavior.

That seems like a reasonable thing to try.  It looks like
NamedLWLockTrancheRequests is copied, too.  Could we used that instead of
adding a new variable?

My guess is that this has been broken since this code was introduced in
commit c1772ad from 2016/v9.6, and AFAIK you are the first to report it, so
I don't feel a tremendous amount of urgency to fix it on the back-branches.

-- 
nathan