From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keld =?iso-8859-1?Q?J=F8rn?= Simonsen Subject: performance of raid10,f2 on 4 disks Date: Wed, 23 Jan 2008 19:21:20 +0100 Message-ID: <20080123182120.GA26044@rap.rap.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hi! I have played around with raid10,f2 on a 2 disk array set, and I really liked the performance on the sequential reads. It looked like double up on the speed, about 173 MB/s for two SATA-2 disks. I then went on to look at my 4 new SATS-2 disks, to have the same kind of performance I made the array by: mdadm --create /dev/md3 --chunk=256 -R -l 10 -n 4 -p f2 /dev/sd[abcd]1 And my first tests showed a sequential read rate of 320 MB/s. Impressive! I then tried it a few more times, but then I could not get more than around 160 MB/s, which is less than what I got on 2 disks. Any ideas of what is going on? Best regards keld