To: pgsql-performance@postgresql.org
From: Ivan Voras <ivoras@freebsd.org>
Subject: Re: Performance block size.
Date: Fri, 27 May 2011 12:54:27 +0200
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On 27/05/2011 00:34, Tory M Blue wrote:
> Working on some optimization as well as finally getting off my
> backside and moving us to 64bit (32gb+memory).
>
> I was reading and at some point it appears on freeBSD  the Postgres
> block size was upped to 16kb, from 8kb. And on my fedora systems I
> believe the default build is 8kb.

This happened some years ago but it was quickly reverted.

There were some apparent gains with the larger block size, especially 
since FreeBSD's UFS uses 16 KiB blocks by default (going to 32 KiB 
really soon now; note that this has no impact on small files because of 
the concept of "block fragments"), but it was concluded that the stock 
installation should follow the defaults set by the developers, not 
porters. YMMV.

> Trying to gain some performance and wondered if any of this tuning
> even is something I should bother with.

Please do some benchmarks and report results.