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Date: Mon, 30 Oct 2006 12:02:11 +1030
From: Greg 'groggy' Lehey <grog@FreeBSD.org>
To: Petri Helenius <pete@he.iki.fi>
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Cc: Steve Peterson <stevep-hv@zpfe.com>, performance@freebsd.org
Subject: Re: gvinum raid5 performance seems slow
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On Saturday, 28 October 2006 at 22:19:17 +0300, Petri Helenius wrote:
>
> According to my understanding vinum does not overlap requests to
> multiple disks when running in raid5 configuration

Yes, it does.  I suspect that gvinum does too.

> so you're not going to achieve good numbers with just "single
> stream" tests.

Single stream tests aren't very good examples for RAID-5, because it
performs writes in two steps: first it reads the old data, then it
writes the new data.

Greg


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