From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keld =?iso-8859-1?Q?J=F8rn?= Simonsen Subject: Re: Upgrading a software RAID Date: Fri, 29 May 2009 10:58:16 +0200 Message-ID: <20090529085815.GA13854@rap.rap.dk> References: <4A1EA095.9090406@usherbrooke.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <4A1EA095.9090406@usherbrooke.ca> Sender: linux-raid-owner@vger.kernel.org To: Maxime Boissonneault Cc: robin@robinhill.me.uk, linux-raid@vger.kernel.org List-Id: linux-raid.ids On Thu, May 28, 2009 at 10:32:53AM -0400, Maxime Boissonneault wrote: > > Robin Hill a =E9crit : >> On Mon May 25, 2009 at 01:05:15PM -0400, Maxime Boissonneault wrote: >> >> =20 >>> Hello, >>> I am using Ubuntu Hardy with 3x500GB drives and the following RAID >>> configuration : >>> >>> /boot is on a 100MB RAID1 >>> / is on a 30GB RAID0 >>> /home is on a 906GB RAID5 >>> >>> =20 >> Ouch - why RAID0 for /? If you lose a single drive then all the >> configuration, etc. is down the drain. I'd suggest rethinking this >> while you're going through the rebuild process anyway. >> >> =20 > That is why I do backups of / on /home regularily. I first did a RAID= 0 =20 > for performance. I did some testing on performance of RAID0,1,5 and =20 > RAID1 was pretty lousy (I put the results of my tests here : =20 > http://cqed.physique.usherbrooke.ca/~mboisson/htpc.php?sec=3Draid_tes= t ) > I guess I should have used a RAID5, but RAID1 seems like a terrible i= dea =20 > considering the really bad performances. Hmm, why not use raid10,f2 for the / system? Then you will get almost raid0 read performance, while write performanc= e is about half of raid0. A setup is described in http://linux-raid.osdl.org/index.php/Preventing_against_a_failing_disk You can do the / system with raid10,f2 with just 2 disks. Best regards keld -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html