Message-ID: <44BB7734.8080801@logix-tt.com>
Date: Mon, 17 Jul 2006 13:40:36 +0200
From: Markus Schaber <schabi@logix-tt.com>
Organization: Logical Tracking and Tracing International AG, Switzerland
User-Agent: Thunderbird 1.5.0.2 (X11/20060516)
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To: Mikael Carneholm <Mikael.Carneholm@WirelessCar.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: RAID stripe size question
References: <7F10D26ECFA1FB458B89C5B4B0D72C2B4E4BD6@sesrv12.wirelesscar.com>
In-Reply-To: <7F10D26ECFA1FB458B89C5B4B0D72C2B4E4BD6@sesrv12.wirelesscar.com>
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Hi, Mikael,

Mikael Carneholm wrote:

> This is something I'd also would like to test, as a common best-practice
> these days is to go for a SAME (stripe all, mirror everything) setup.
> From a development perspective it's easier to use SAME as the developers
> won't have to think about physical location for new tables/indices, so
> if there's no performance penalty with SAME I'll gladly keep it that
> way.

Usually, it's not the developers task to care about that, but the DBAs
responsibility.

>> And look into the commit_delay/commit_siblings settings, they allow you
> to deal latency for throughput (means a little more latency per
> transaction, but much more transactions per second throughput for the
> whole system.)
> 
> In a previous test, using cd=5000 and cs=20 increased transaction
> throughput by ~20% so I'll definitely fiddle with that in the coming
> tests as well.

How many parallel transactions do you have?

Markus


-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org