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Date: Tue, 26 May 2026 23:36:49 +0200
Message-Id: <DISXKTNN3JUM.30KZW8W94LPVO@jeltef.nl>
From: "Jelte Fennema-Nio" <postgres@jeltef.nl>
Cc: "PostgreSQL-development" <pgsql-hackers@postgresql.org>
Subject: Re: future of PQfn()
To: "Nathan Bossart" <nathandbossart@gmail.com>
MIME-Version: 1.0
References: <ahXE28klgxIJXBLq@nathan>
In-Reply-To: <ahXE28klgxIJXBLq@nathan>
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On Tue, 26 May 2026 at 18:05, Nathan Bossart <nathandbossart@gmail.com>=20
wrote:
> Another approach we
> could take is to just send the query via PQexecParams(), but a simple tes=
t
> (creating and unlinking 10K LOs) showed a ~41% slowdown compared to HEAD.
> So, I guess we'll need to keep PQnfn() around for now...
>
> Thoughts?

I had a small WIP patch (fully AI generated and not yet vetted by me)
lying around for unrelated reasons to make the extended protocol perform
closer to the simple protocol with pgbench --select-only by using
CreateOneShotCachedPlan to create the plan for unnamed prepared
statements (see attached).

Could you share the simple LO test you were running here and/or rerun it
with this patch applied? I'd love to know if the patch reduces the
slowdown significantly, or if something else is the bottleneck.

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