Horton

Re: pgbench - add pseudo-random permutation function

Fabien COELHO <coelho@cri.ensmp.fr>

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From: Fabien COELHO <coelho@cri.ensmp.fr>
To: Dean Rasheed <dean.a.rasheed@gmail.com>
Cc: Alvaro Herrera <alvherre@2ndquadrant.com>, Thomas Munro <thomas.munro@gmail.com>, David Steele <david@pgmasters.net>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Hironobu SUZUKI <hironobu@interdb.jp>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-04-06T21:31:31Z
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. pgbench: Function to generate random permutations.

  2. Add basic support for using the POPCNT and SSE4.2s LZCNT opcodes

  3. Further improve code for probing the availability of ARM CRC instructions.

Hello Dean,

> Pushed.
>
> I decided not to go with the "joke" randu64() function, but instead
> used getrand() directly. This at least removes any *direct* use of
> doubles in permute() (though of course they're still used indirectly),
> and means that if getrand() is improved in the future, permute() will
> benefit too.

Good idea, at least it is hidden and in one place.

Thanks for the push!

-- 
Fabien.