From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Wed, 01 Oct 2008 12:34:44 -0700 (PDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.168.28]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id m91JYdXE002850 for ; Wed, 1 Oct 2008 12:34:41 -0700 Received: from one.firstfloor.org (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id ABCF11306B3B for ; Wed, 1 Oct 2008 12:36:16 -0700 (PDT) Received: from one.firstfloor.org (one.firstfloor.org [213.235.205.2]) by cuda.sgi.com with ESMTP id vTZa80mHs1ON3B5e for ; Wed, 01 Oct 2008 12:36:16 -0700 (PDT) Subject: Re: RAID5/6 writes From: Andi Kleen References: <20081001175237.GJ32037@cordes.ca> Date: Wed, 01 Oct 2008 21:36:13 +0200 In-Reply-To: <20081001175237.GJ32037@cordes.ca> (Peter Cordes's message of "Wed, 01 Oct 2008 14:52:37 -0300") Message-ID: <87k5csp0pe.fsf@basil.nowhere.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: Peter Cordes Cc: xfs@oss.sgi.com Peter Cordes writes: > > XFS knows (or should have been told by the admin with mkfs!) what the > stripe geometry is: block size and stripe width. So it could apply > this optimization only if it would make a write cover more whole > blocks or whole stripes. It's a nice idea, but I don't think XFS knows the actual RAID level, only the stripes. And for 0/1 it wouldn't be a good idea. -Andi