Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932101AbWAQX2I (ORCPT ); Tue, 17 Jan 2006 18:28:08 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932226AbWAQX2I (ORCPT ); Tue, 17 Jan 2006 18:28:08 -0500 Received: from free.wgops.com ([69.51.116.66]:42505 "EHLO shell.wgops.com") by vger.kernel.org with ESMTP id S932101AbWAQX2G (ORCPT ); Tue, 17 Jan 2006 18:28:06 -0500 Date: Tue, 17 Jan 2006 16:27:39 -0700 From: Michael Loftis To: linux-kernel@vger.kernel.org Subject: Re: FYI: RAID5 unusably unstable through 2.6.14 Message-ID: In-Reply-To: References: X-Mailer: Mulberry/4.0.4 (Mac OS X) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-MailScanner-Information: Please contact support@wgops.com X-MailScanner: WGOPS clean X-MailScanner-From: mloftis@wgops.com Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1031 Lines: 27 --On January 17, 2006 1:35:46 PM -0600 Cynbe ru Taren wrote: > > Just in case the RAID5 maintainers aren't aware of it: > > The current Linux kernel RAID5 implementation is just > too fragile to be used for most of the applications > where it would be most useful. > > In principle, RAID5 should allow construction of a > disk-based store which is considerably MORE reliable > than any individual drive. Absolutely not. The more spindles the more chances of a double failure. Simple statistics will mean that unless you have mirrors the more drives you add the more chance of two of them (really) failing at once and choking the whole system. That said, there very well could be (are?) cases where md needs to do a better job of handling the world unravelling. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/