Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754666Ab0DMBWk (ORCPT ); Mon, 12 Apr 2010 21:22:40 -0400 Received: from bld-mail13.adl6.internode.on.net ([150.101.137.98]:50499 "EHLO mail.internode.on.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754647Ab0DMBWh (ORCPT ); Mon, 12 Apr 2010 21:22:37 -0400 Date: Mon, 12 Apr 2010 10:22:25 +1000 From: Dave Chinner To: Thomas Gleixner Cc: Avi Kivity , Ben Gamari , Andi Kleen , Arjan van de Ven , LKML , tytso@mit.edu, npiggin@suse.de, Ingo Molnar , Ruald Andreae , Jens Axboe , Olly Betts , martin f krafft Subject: Re: Poor interactive performance with I/O loads with fsync()ing Message-ID: <20100412002225.GB2493@dastard> References: <4b9fa440.12135e0a.7fc8.ffffe745@mx.google.com> <4baeaee5.c5c2f10a.7187.2688@mx.google.com> <20100327204233.0d84542a@infradead.org> <4baf624c.48c3f10a.16d0.ffffccb8@mx.google.com> <87y6hcyu85.fsf@basil.nowhere.org> <4bbf401e.a3b9e70a.13f3.4460@mx.google.com> <4BC1E4A4.1070103@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1711 Lines: 43 On Sun, Apr 11, 2010 at 08:16:09PM +0200, Thomas Gleixner wrote: > On Sun, 11 Apr 2010, Avi Kivity wrote: > > On 04/09/2010 05:56 PM, Ben Gamari wrote: > > > On Mon, 29 Mar 2010 00:08:58 +0200, Andi Kleen wrote: > > > > Ben Gamari writes: > > > > ext4/XFS/JFS/btrfs should be better in this regard > > > > > > > I am using btrfs, so yes, I was expecting things to be better. > > > Unfortunately, > > > the improvement seems to be non-existent under high IO/fsync load. > > > > btrfs is known to perform poorly under fsync. > > XFS does not do much better. Just moved my VM images back to ext for > that reason. Numbers? Workload description? Mount options? I hate it when all I hear is "XFS sucked, so I went back to extN" reports without any more details - it's hard to improve anything without any details of the problems. Also worth remembering is that XFS defaults to slow-but-safe options, but ext3 defaults to fast-and-I-don't-give-a-damn-about- data-safety, so there's a world of difference between the filesystem defaults.... And FWIW, I run all my VMs on XFS using default mkfs and mount options, and I can't say that I've noticed any performance problems at all despite hammering the IO subsystems all the time. The only thing I've ever done is occasionally run xfs_fsr across permanent qcow2 VM images to defrag them as the grow slowly over time... Cheers, Dave. -- Dave Chinner david@fromorbit.com -- 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/