From mboxrd@z Thu Jan  1 00:00:00 1970
From: "3tcdgwg3" <3tcdgwg3@prodigy.net>
Subject: Software RAID level performance
Date: Thu, 6 Nov 2003 23:29:39 -0800
Sender: linux-raid-owner@vger.kernel.org
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Cc: 'Linux raid mailing list' <linux-raid@vger.kernel.org>, Paul Clements <Paul.Clements@SteelEye.com>
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Hello,

I have a question regarding the RAID1 performance.

I tought the RAID1 will access disk in a con-current way, but
today I installed a 2.4-18 (Redhat 9.0). Seems RAID1 code
is not doing the disk access in a balanced way? I see single disk
is faster the RAID1.  
First,  do dd, read from /dev/zero write to disk, 
then  dd again,  read from disk write write to /dev/null,
in both cases, single disk out run 2 disk RAID1.

Any one can help me to understand this?

Thank you so much.