Date: Fri, 20 Feb 2026 12:15:41 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Nazir Bilal Yavuz <byavuz81@gmail.com>
Cc: Manni Wood <manni.wood@enterprisedb.com>, KAZAR Ayoub <ma_kazar@esi.dz>,
	Neil Conway <neil.conway@gmail.com>,
	Andrew Dunstan <andrew@dunslane.net>,
	Shinya Kato <shinya11.kato@gmail.com>,
	PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: Speed up COPY FROM text/CSV parsing using SIMD
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On Fri, Feb 20, 2026 at 12:50:35PM +0300, Nazir Bilal Yavuz wrote:
> On Fri, 20 Feb 2026 at 03:09, Manni Wood <manni.wood@enterprisedb.com> wrote:
>> Nazir, I ran my benchmarks with more rows this time --- as many rows as
>> would fit on  my test computers without exhausting their RAM disks. That
>> seems to have brought things more into line with what Ayoub saw. I did
>> get some small regressions, but I suspect those are not a big deal. (For
>> instance, on both machines I also noticed the occasional "truncate
>> table" would take longer than the others, despite my scripts' best
>> efforts to steady a CPU core and pin postmaster and children to that
>> core.)

Yeah, the couple of small regressions seem close to (or below) the noise
level, and IIUC yours were the only benchmarks that showed them, anyway.
Plus, I think we'll need this change regardless as a prerequisite for the
SIMD work.

> Thank you both for the benchmarks. Results look good to me!

Committed that part.

-- 
nathan