Re: Change GUC hashtable to use simplehash?

Anton A. Melnikov <a.melnikov@postgrespro.ru>

From: "Anton A. Melnikov" <a.melnikov@postgrespro.ru>
To: John Naylor <johncnaylorls@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Jeff Davis <pgsql@j-davis.com>, Ants Aasma <ants.aasma@cybertec.at>, Heikki Linnakangas <hlinnaka@iki.fi>, Junwang Zhao <zhjwpku@gmail.com>, jian he <jian.universality@gmail.com>, Andres Freund <andres@anarazel.de>, Gurjeet Singh <gurjeet@singh.im>, pgsql-hackers@postgresql.org
Date: 2025-02-14T11:40:52Z
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. Silence warning in older versions of Valgrind

  2. Revert "Speed up tail processing when hashing aligned C strings, take two"

  3. Speed up tail processing when hashing aligned C strings, take two

  4. Teach fasthash_accum to use platform endianness for bytewise loads

  5. Add macro to disable address safety instrumentation

  6. Convert uses of hash_string_pointer to fasthash equivalent

  7. Speed up tail processing when hashing aligned C strings

  8. Add helper functions for dshash tables with string keys.

  9. Fix warnings in cpluspluscheck

  10. Further cosmetic review of hashfn_unstable.h

  11. Simplify initialization of incremental hash state

  12. Add optimized C string hashing

  13. Add inline incremental hash functions for in-memory use

  14. Make all Perl warnings fatal

Hi, Jhon!

On 14.02.2025 08:17, John Naylor wrote:
> Hi Anton, could you please test if the attached passes for you? This
> seems the simplest way.

Yes, of course. I tested this patch on the current master at 9e17ac997
in the same way and found no valgrind errors.

Moreover, with -O2 build on my PC the nsphash_lookup() has
become fully inlined with this patch and almost two time
faster - 112 asm instructions under the same conditions.
Thanks!

With the best wishes,

-- 
Anton A. Melnikov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company