Feedback-ID: id4a34324:Fastmail
Date: Thu, 12 Feb 2026 16:25:49 -0500
From: Andres Freund <andres@anarazel.de>
To: KAZAR Ayoub <ma_kazar@esi.dz>
Cc: Pg Hackers <pgsql-hackers@postgresql.org>, 
	Nathan Bossart <nathandbossart@gmail.com>, Neil Conway <neil.conway@gmail.com>, 
	Manni Wood <manni.wood@enterprisedb.com>, Andrew Dunstan <andrew@dunslane.net>, 
	Shinya Kato <shinya11.kato@gmail.com>, Mark Wong <markwkm@gmail.com>, 
	Nazir Bilal Yavuz <byavuz81@gmail.com>
Subject: Re: Speed up COPY TO text/CSV parsing using SIMD
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Hi,

On 2026-02-12 22:07:52 +0100, KAZAR Ayoub wrote:
> Currently optimizing COPY FROM using SIMD is still under review, but for
> the case of COPY TO using the same ideas, we found that the problem is
> trivial, the attached patch gives very nice speedups as confirmed by
> Manni's benchmarks.

I have a hard time believing that adding a strlen() to the handling of a short
column won't be a measurable overhead with lots of short attributes.
Particularly because the patch afaict will call it repeatedly if there are any
to-be-escaped characters.

I also don't think it's good how much code this repeats. I think you'd have to
start with preparatory moving the exiting code into static inline helper
functions and then introduce SIMD into those.

Greetings,

Andres Freund