From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell Coker Subject: Re: Raid5, LVM and Reiserfs Date: Mon, 21 Oct 2002 07:51:39 +0200 Message-ID: <200210210751.39155.bofh@coker.com.au> References: <000701c277c9$ef8d6c70$0101a8c0@bummer> <200210210449.g9L4n50g022158@turing-police.cc.vt.edu> <3DB392F6.3000603@namesys.com> Reply-To: Russell Coker Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <3DB392F6.3000603@namesys.com> List-Id: Content-Type: text/plain; charset="us-ascii" To: Hans Reiser , Valdis.Kletnieks@vt.edu, Reiserfs mail-list On Mon, 21 Oct 2002 07:39, Hans Reiser wrote: > >You may wish to verify further. Has the hardware raid controller been > >identified as being slower than *software* RAID-5? (Remember - if you do > >it in software, you have to do a disk write per disk). Or is the RAID > >controller merely "not as fast as other hardware RAID controllers)? > > It would be surprising if any hardware RAID controller was as bad as > software RAID. I agree that measuring is advisable. I would be > curious to see numbers on something like that. It's fairly common for low-end RAID hardware to have limitations of memory or CPU bandwidth that limit the bulk IO rate. Hardware RAID that can only sustain 10M/s was quite common until very recently. However such hardware RAID did well on random IO tests, so the result you get depends on what exactly you do (as usual). -- http://www.coker.com.au/bonnie++/ Bonnie++ hard drive benchmark http://www.coker.com.au/postal/ Postal SMTP/POP benchmark http://www.coker.com.au/projects.html Projects I am working on http://www.coker.com.au/~russell/ My home page