Re: Improve CRC32C performance on SSE4.2

John Naylor <johncnaylorls@gmail.com>

From: John Naylor <johncnaylorls@gmail.com>
To: "Devulapalli, Raghuveer" <raghuveer.devulapalli@intel.com>
Cc: Nathan Bossart <nathandbossart@gmail.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>, "Shankaran, Akash" <akash.shankaran@intel.com>
Date: 2025-03-24T11:37:42Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Include _mm512_zextsi128_si512() in AVX-512 configure probes.

  2. Properly fix AVX-512 CRC calculation bug

  3. Workaround code generation bug in clang

  4. Compute CRC32C using AVX-512 instructions where available

  5. Inline CRC computation for small fixed-length input on x86

  6. Be more paranoid in configure's checks for CRC and POPCNT intrinsics.

On Thu, Mar 13, 2025 at 11:38 PM Devulapalli, Raghuveer
<raghuveer.devulapalli@intel.com> wrote:
>
>  > > I've gone ahead and added the generated AVX-512 algorithm in
>  > > v14-0005
>
> Here is my benchmark numbers (master v/s v14) on TGL (time in ms):
>
> Buf-size-bytes  Master  v14
> 64      9.547   6.095
...
> 256     31.399  10.035

Thanks for testing! Looks good. I'll take a look at the configure
checks soon, since I had some questions there.

-- 
John Naylor
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