Re: random() function documentation

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Cc: pgsql-hackers@lists.postgresql.org
Date: 2022-04-11T18:45:19Z
Lists: pgsql-hackers
=?utf-8?Q?Dagfinn_Ilmari_Manns=C3=A5ker?= <ilmari@ilmari.org> writes:
> I just noticed that the since the random() rewrite¹, the documentation's
> claim² that it "uses a simple linear congruential algorithm" is no
> longer accurate (xoroshiro128** is an xorshift variant, which is a
> linear-feedback shift register algorithm).

> I don't have a suggestion for the exact wording, since I don't know
> whether xoroshiro128** qualifies as "simple", or to what level of
> specificity we want to document the algorithm.

How about we just say "uses a linear-feedback shift register algorithm"?
"Simple" is in the eye of the beholder anyway.

			regards, tom lane



Commits

  1. Doc: update description of random() function.

  2. Replace random(), pg_erand48(), etc with a better PRNG API and algorithm.