From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matti Aarnio Subject: Re: RAID1 VS RAID5 Date: Sun, 26 Oct 2003 18:55:37 +0200 Sender: linux-raid-owner@vger.kernel.org Message-ID: <20031026165537.GW26480@mea-ext.zmailer.org> References: <1067179519.1222.107.camel@cala> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1067179519.1222.107.camel@cala> To: Mario Giammarco Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Sun, Oct 26, 2003 at 03:45:19PM +0100, Mario Giammarco wrote: > Hello, > I would like to buy new SCSI hard disk to be used with lsi 160 > controller in 32 bit pci. > > I can choose: > > - RAID5 of three Maxtor Atlas 10K II 9gb > - RAID1 of two Maxtro Atlas 10K III 18gb > > My problem is: I have seen that RAID1 code does not interleave reads so > it does not improve performance very much putting two hard disks. Performance boosting isn't primary goal in RAID schemes involving data replication. For RAID1 a suitably chosen read-interleave could be used to improve _large_ file reads, of course. Another strategy is to distribute read operations to all online disks forming up the RAID1 set with elevators of their own. > Is there a patch to change raid1 behaviour? If it feels important, such can be made. > In linux 2.6.0 is it better? It can be made, if it isn't. > Thanks in advance for any reply. > -- > Mario Giammarco /Matti Aarnio