Re: [PATCH v4] Avoid manual shift-and-test logic in AllocSetFreeIndex

From: Jeremy Kerr <jk(at)ozlabs(dot)org>
To: Greg Stark <gsstark(at)mit(dot)edu>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Stefan Kaltenbrunner <stefan(at)kaltenbrunner(dot)cc>, Robert Haas <robertmhaas(at)gmail(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: [PATCH v4] Avoid manual shift-and-test logic in AllocSetFreeIndex
Date: 2009-07-21 03:08:11
Message-ID: 200907211308.12371.jk@ozlabs.org
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Hi Greg,

Thanks for the benchmark app, thought I'd pitch in with some ppc
results:

> clz 1.530s
> lookup table 1.720s
> float hack 4.424s
> unrolled 5.280s
> normal 5.369s

POWER5+:
clz 2.046s
lookup table 2.188s
float hack 7.786s
unrolled 6.353s
normal 7.033s

POWER6:
clz 1.063s
lookup table 1.199s
float hack 3.575s
unrolled 2.290s
normal 3.456s

Cheers,

Jeremy

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2009-07-21 04:51:46 Re: [PATCH] SE-PgSQL/tiny rev.2193
Previous Message Tom Lane 2009-07-21 03:07:36 Re: [PATCH v4] Avoid manual shift-and-test logic in AllocSetFreeIndex