Date: Tue, 2 Dec 2025 10:31:33 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Rahila Syed <rahilasyed90@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: show size of DSAs and dshash tables in
 pg_dsm_registry_allocations
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On Tue, Dec 02, 2025 at 02:28:29PM +0530, Rahila Syed wrote:
> Thank you for highlighting the discussions. I'm unsure about the best
> approach here, but I think it would be safe to stay consistent with the
> rest of the code in dsa.c, especially since it's unclear that the use of
> LW_EXCLUSIVE for reading values in dsa is a mistake.

Okay.  I switched to LW_EXCLUSIVE and will consider starting a new thread
to use LW_SHARED when possible in dsa.c.

> Sorry for the confusion, I am trying to say that we can change the
> following comment
> 
> + *The area must have
> + * been created with dsa_create (not dsa_create_in_place).
> 
> to say this:
> 
> "The area must have been created using dsm_segments"
> 
> Since, this function can report the size of an area created with
> dsa_create_in_place too, as long as the area is created using
> dsm_segments.

It cannot report the size of in-place areas, at least not without some
changes, because (AFAICT) there's no way to get a dsa_handle for an
in-place segment.

I've now committed the patch.  Thanks everyone for reviewing!

-- 
nathan