From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id n7KEc14T100081 for ; Thu, 20 Aug 2009 09:38:11 -0500 Received: from mail.rtr.ca (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 31F703E64E2 for ; Thu, 20 Aug 2009 07:38:22 -0700 (PDT) Received: from mail.rtr.ca (rtr.ca [76.10.145.34]) by cuda.sgi.com with ESMTP id uoKJ4IOnEwewrGzR for ; Thu, 20 Aug 2009 07:38:22 -0700 (PDT) Message-ID: <4A8D5FDB.7080505@rtr.ca> Date: Thu, 20 Aug 2009 10:38:19 -0400 From: Mark Lord MIME-Version: 1.0 Subject: Re: [PATCH, RFC] xfs: batched discard support References: <20090816004705.GA7347@infradead.org> <20090819203916.GA25296@elte.hu> <4A8CA956.2060406@rtr.ca> <4A8D5442.1000302@redhat.com> In-Reply-To: <4A8D5442.1000302@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Ric Wheeler Cc: Peter Zijlstra , linux-scsi@vger.kernel.org, Neil Brown , linux-kernel@vger.kernel.org, xfs@oss.sgi.com, Christoph Hellwig , IDE/ATA development list , Paul Mackerras , jens.axboe@oracle.com, linux-fsdevel@vger.kernel.org, Ingo Molnar , Linus Torvalds Ric Wheeler wrote: > > Note that returning consistent data is critical for devices that are > used in a RAID group since you will need each RAID block that is used to > compute the parity to continue to return the same data until you > overwrite it with new data :-) > > If we have a device that does not support this (or is misconfigured not > to do this), we should not use those devices in an MD group & do discard > against it... .. Well, that's a bit drastic. But the RAID software should at least not issue TRIM commands in ignorance of such. Would it still be okay to do the TRIMs when the entire parity stripe (across all members) is being discarded? (As opposed to just partial data there being dropped) _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs