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Date: Fri, 13 Mar 2026 13:21:38 -0400
From: "Greg Burd" <greg@burd.me>
To: "Nazir Bilal Yavuz" <byavuz81@gmail.com>
Cc: "Nathan Bossart" <nathandbossart@gmail.com>,
 "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>,
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Subject: Re: Speed up COPY FROM text/CSV parsing using SIMD
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On Fri, Mar 13, 2026, at 12:14 PM, Nazir Bilal Yavuz wrote:
> Hi Greg,

Hello Nazir,

> On Fri, 13 Mar 2026 at 18:29, Greg Burd <greg@burd.me> wrote:
>>
>> I've always been a fan of these kinds of optimization so I couldn't resist reviewing, but I know you're ready to commit so I'll just check on some systems I have. :)
>
> Thank you for the review!

Thank YOU for the work fixing this. :)

>> At first glance the implementation seems conservative, but correct and safe. Local testing on on Linux/FreeBSD x86_64, and Win11/aarch64/MSVC seem good. I also tried IllumOS/SPARCv9 and with some fixes (from another active thread) to the build system and it worked just fine too.  I'm sure the 10 people care will be thrilled. ;-
>
> Yes, we can probably improve this further with heuristics, but for now
> we wanted to avoid introducing any potential regressions.
>> I also created a few tests (attached) to check boundary conditions, I might add some along with the RISC-V work.
>
> Thank you for the tests! I have checked them and the output is the
> same on both v17 and master. Do you think it would make sense to add
> them as regression tests?

If there are tests that materially add to the coverage that's a good thing to consider adding.  I don't think all those tests are necessary.

best.

-greg

> -- 
> Regards,
> Nazir Bilal Yavuz
> Microsoft