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Date: Mon, 12 Feb 2001 10:34:10 +0100 (CET)
From: arjan@fenrus.demon.nl (Arjan van de Ven)
To: ppetru@ppetru.net (Petru Paler)
Subject: Re: RAID1 read balancing
cc: linux-kernel@vger.kernel.org
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In-Reply-To: <20010211161242.A949@ppetru.net>
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In article <20010211161242.A949@ppetru.net> you wrote:

> For a RAID1 array built of two disks on two separate SCSI controllers,
> are the reads balanced between the two controllers (for higher speed) ?

With the current RAID1 setup, you will NOT get a speed increase for
single-threaded, sequential reading programs (read: benchmarks like hdparm
and tiobench)[1]. You will get improvents in all other cases.

Greetings,
   Arjan van de Ven


[1] This can be fix by a 10 line patch, however this changes the on-disk
layout.
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