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From: Nazir Bilal Yavuz <byavuz81@gmail.com>
Date: Tue, 19 Aug 2025 17:14:54 +0300
Message-ID: 
 <CAN55FZ109W90Ux_EBEqkkU2TyNqBNhdhN_1XPRGo3iiZ2L9b=A@mail.gmail.com>
Subject: Re: Speed up COPY FROM text/CSV parsing using SIMD
To: KAZAR Ayoub <ma_kazar@esi.dz>
Cc: Shinya Kato <shinya11.kato@gmail.com>, pgsql-hackers@postgresql.org
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Hi,

On Tue, 19 Aug 2025 at 15:33, Nazir Bilal Yavuz <byavuz81@gmail.com> wrote:
>
> I am able to reproduce the regression you mentioned but both
> regressions are %20 on my end. I found that (by experimenting) SIMD
> causes a regression if it advances less than 5 characters.
>
> So, I implemented a small heuristic. It works like that:
>
> - If advance < 5 -> insert a sleep penalty (n cycles).

'sleep' might be a poor word choice here. I meant skipping SIMD for n
number of times.

-- 
Regards,
Nazir Bilal Yavuz
Microsoft