Received: with ECARTIS (v1.0.0; list xfs); Wed, 27 Jun 2007 16:29:44 -0700 (PDT) X-Spam-Checker-Version: SpamAssassin 3.2.0-pre1-r499012 (2007-01-23) on oss.sgi.com X-Spam-Level: X-Spam-Status: No, score=0.2 required=5.0 tests=AWL,BAYES_50 autolearn=no version=3.2.0-pre1-r499012 Received: from postoffice.aconex.com (mail.app.aconex.com [203.89.192.138]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id l5RNTbtL012194 for ; Wed, 27 Jun 2007 16:29:39 -0700 Received: from edge.yarra.acx (unknown [203.89.192.141]) by postoffice.aconex.com (Postfix) with ESMTP id 3E18F92C3CF; Thu, 28 Jun 2007 09:29:39 +1000 (EST) Subject: Re: [PATCH 4/7][TAKE5] support new modes in fallocate From: Nathan Scott Reply-To: nscott@aconex.com To: David Chinner , Andreas Dilger Cc: xfs-oss , "Amit K. Arora" , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, suparna@in.ibm.com, cmm@us.ibm.com In-Reply-To: <20070627133657.GQ989688@sgi.com> References: <20070613235217.GS86004887@sgi.com> <20070614091458.GH5181@schatzie.adilger.int> <20070614120413.GD86004887@sgi.com> <20070614193347.GN5181@schatzie.adilger.int> <20070625132810.GA1951@amitarora.in.ibm.com> <20070625134500.GE1951@amitarora.in.ibm.com> <20070625150320.GA8686@amitarora.in.ibm.com> <20070625214626.GJ5181@schatzie.adilger.int> <20070626231431.GO31489@sgi.com> <20070627034915.GR6652@schatzie.adilger.int> <20070627133657.GQ989688@sgi.com> Content-Type: text/plain Organization: Aconex Date: Thu, 28 Jun 2007 09:28:36 +1000 Message-Id: <1182986916.15488.88.camel@edge.yarra.acx> Mime-Version: 1.0 X-Mailer: Evolution 2.6.3 Content-Transfer-Encoding: 7bit X-Virus-Scanned: ClamAV version 0.90, clamav-milter version devel-120207 on oss.sgi.com X-Virus-Status: Clean X-archive-position: 11958 X-ecartis-version: Ecartis v1.0.0 Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com X-original-sender: nscott@aconex.com Precedence: bulk X-list: xfs On Wed, 2007-06-27 at 23:36 +1000, David Chinner wrote: > .... Allows setup_swap_extents() to use preallocated files on XFS > filesystems for swap files without ever needing to convert them. Using unwritten extents (as opposed to the MKSWAP flag mentioned earlier) has the unfortunate down side of requiring transactions, possibly additional IO, and memory allocation during swap. (but, this patch should probably go in regardless, as teaching generic code about unwritten extents is not a bad idea). cheers. -- Nathan