From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263425AbTJVPYX (ORCPT ); Wed, 22 Oct 2003 11:24:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263467AbTJVPYX (ORCPT ); Wed, 22 Oct 2003 11:24:23 -0400 Received: from virt-216-40-198-21.ev1servers.net ([216.40.198.21]:31499 "EHLO virt-216-40-198-21.ev1servers.net") by vger.kernel.org with ESMTP id S263425AbTJVPYH (ORCPT ); Wed, 22 Oct 2003 11:24:07 -0400 Date: Wed, 22 Oct 2003 10:17:43 -0500 From: Chuck Campbell To: linux-kernel@vger.kernel.org Subject: Re: Software RAID5 with 2.6.0-test Message-ID: <20031022151743.GA21348@helium.inexs.com> Reply-To: campbell@accelinc.com Mail-Followup-To: Chuck Campbell , linux-kernel@vger.kernel.org References: <1065690658.10389.19.camel@slurv> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 21, 2003 at 09:36:39PM +0000, bill davidsen wrote: > In article , > =?iso-8859-1?q?M=E5ns_Rullg=E5rd?= wrote: > | Bill Davidsen writes: > > Unfortunately my experience is with either the cheap motherboard ones I > get for free and the IBM ServRAID controllers which are kind of in the > "more than that" category. The benefit of the m/b ones is that with > RAID-1 you will get a boot if the boot drive fails. Period. Unlike > optimal RAID-1 which will read mirrored data from any non-busy drive, > the cheap ones seem to do fail-over only, and read the second drive > only if the first fails, or even require both drives to be on the same > cable, ensuring that the bus will be busy when either drive is busy. > They do buy reliability, however, so there are places where they are > very cost effective. In this situation that you describe, how does one recover from this? Do these cheap motherboard RAID-1's do an autorebuild when the failed disk is replaced? (Obviously not hot-swap, but on reboot to replace the drive). > > The IBM controllers are everything you ever wanted in a controller. It > supports four SCSI busses for bandwidth, all the RAID types including > 5e, and it has Linux config software so you can do most reconfigures on > a running system. I would choose them over anything else I've personally > used, mainly Adaptec and PERC. They are really great for multi-TB > storage systems. Do they compare favorable against 3Ware as well? > Anyone who says that any one solution is best for everything is clearly > misguided, but I do think that for many midsize applications that > software RAID is the most cost effective solution, and vs. moderately > priced controllers very likely to be the higher performance solution as > well. Is this statement true, in your opinion, for RAID-5 as well? -chuck --