Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752950AbYLQV24 (ORCPT ); Wed, 17 Dec 2008 16:28:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752082AbYLQV2c (ORCPT ); Wed, 17 Dec 2008 16:28:32 -0500 Received: from acsinet14.oracle.com ([141.146.126.236]:58131 "EHLO acsinet14.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751949AbYLQV2a (ORCPT ); Wed, 17 Dec 2008 16:28:30 -0500 Subject: Re: Notes on support for multiple devices for a single filesystem From: Chris Mason To: Kay Sievers Cc: Andrew Morton , Christoph Hellwig , adilger@sun.com, sfr@canb.auug.org.au, linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org In-Reply-To: References: <1227183484.6161.17.camel@think.oraclecorp.com> <1228962896.21376.11.camel@think.oraclecorp.com> <20081211141436.030c2d65.sfr@canb.auug.org.au> <20081210200604.8e190b0d.akpm@linux-foundation.org> <1229006596.22236.46.camel@think.oraclecorp.com> <20081215210323.GB5000@webber.adilger.int> <20081217132343.GA14695@infradead.org> <20081217115325.3312858a.akpm@linux-foundation.org> <1229547485.27170.77.camel@think.oraclecorp.com> Content-Type: text/plain Date: Wed, 17 Dec 2008 16:26:24 -0500 Message-Id: <1229549184.27170.88.camel@think.oraclecorp.com> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1 Content-Transfer-Encoding: 7bit X-Source-IP: acsinet11.oracle.com [141.146.126.233] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090205.49496EFA.00AC:SCFMA922111,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2008-12-17 at 22:20 +0100, Kay Sievers wrote: > On Wed, Dec 17, 2008 at 21:58, Chris Mason wrote: > > On Wed, 2008-12-17 at 11:53 -0800, Andrew Morton wrote: > > > > There are other bits and pieces like high speed front end caching > > devices that would be difficult in MD/LVM, but since I don't have that > > coded yet I suppose they don't really count... > > Features like the very nice and useful directory-based snapshots would > also not be possible with simple block-based multi-devices, right? At least for btrfs, the snapshotting is independent from the multi-device code, and you still get snapshotting on single device filesystems. -chris -- 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/