From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030922AbXDPTwk (ORCPT ); Mon, 16 Apr 2007 15:52:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030923AbXDPTwk (ORCPT ); Mon, 16 Apr 2007 15:52:40 -0400 Received: from lazybastard.de ([212.112.238.170]:55245 "EHLO longford.lazybastard.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030922AbXDPTwj (ORCPT ); Mon, 16 Apr 2007 15:52:39 -0400 Date: Mon, 16 Apr 2007 21:46:45 +0200 From: =?utf-8?B?SsO2cm4=?= Engel To: Tomasz =?utf-8?Q?K=C5=82oczko?= Cc: Christoph Hellwig , Stefan Richter , Jan Engelhardt , Mike Snitzer , Neil Brown , "David R. Litwin" , linux-kernel@vger.kernel.org Subject: Re: ZFS with Linux: An Open Plea Message-ID: <20070416194644.GA27843@lazybastard.org> References: <17952.5537.364603.419364@notabene.brown> <170fa0d20704140704l29d9db76q59195a3d9cad868a@mail.gmail.com> <46238204.9060907@s5r6.in-berlin.de> <20070416145527.GA26863@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 16 April 2007 17:46:50 +0200, Tomasz Kłoczko wrote: > On Mon, 16 Apr 2007, Christoph Hellwig wrote: > > >Numbers, please. So far in all interesting benchmarks it actually > >was slower. But when they're faster than XFS somewhere I'd defintly > >be interesting in looking at why this is true and if possible and > >important enough fix it. Christoph, could you show some numbers as well? While I usually trust your opinion, I have yet to see any substantial argument against ZFS from your side. > http://cmynhier.blogspot.com/2006/05/zfs-io-reordering-benchmark.html http://blogs.sun.com/bill/#zfs_vs_the_benchmark If you read closely you may notice that ZFS had relatively little to do with read performance under heavy write load. ZFS simply has "some fancy I/O scheduling code" that in particular deals with deadlines. The Linux equivalent appears to be CONFIG_IOSCHED_DEADLINE. But the quoted benchmark does not mention which scheduler was used for Linux. So unless the benchmark is redone and properly documented, its numbers are fairly worthless. Bummer. > http://cmynhier.blogspot.com/2006/05/zfs-benchmarking.html "The company I work for would probably balk if I put that script here" No publically available benchmark. So even if a third party wanted to, it couldn't recreate the benchmark. Again, fairly worthless. So by my count, neither side has showed any worthwile numbers. Whether ZFS performance is better or worse is anyone's guess. Jörn -- Simplicity is prerequisite for reliability. -- Edsger W. Dijkstra