Re: CPU costs of random_zipfian in pgbench

Fabien COELHO <coelho@cri.ensmp.fr>

From: Fabien COELHO <coelho@cri.ensmp.fr>

To: Alvaro Herrera <alvherre@2ndquadrant.com>

Cc: Tom Lane <tgl@sss.pgh.pa.us>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Georgios Kokolatos <gkokolatos@pm.me>, PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>

Date: 2019-04-03T19:54:54Z

Lists: pgsql-hackers

Attachments

pgbench-zipf-simpler-1.patch (text/x-diff) patch

> Ah, so we now we can get rid of the TState * being passed around
> separately for expression execution, too?

Indeed.

I would have thought that the compiler would have warned if it is unused, 
but because of the recursion it is uselessly used.

Ok, maybe the sentence above is not very clear. Attached a patch which 
simplifies further.

-- 
Fabien.

Commits

Remove now-unnecessary thread pointer arguments in pgbench.
- d8c0bd9fefa9 12.0 landed
Restrict pgbench's zipfian parameter to ensure good performance.
- 26a76cb64072 12.0 landed