Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934595AbZDAVkJ (ORCPT ); Wed, 1 Apr 2009 17:40:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934105AbZDAVj1 (ORCPT ); Wed, 1 Apr 2009 17:39:27 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:55492 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934575AbZDAVj0 (ORCPT ); Wed, 1 Apr 2009 17:39:26 -0400 Date: Wed, 1 Apr 2009 14:36:22 -0700 From: Andrew Morton To: lsorense@csclub.uwaterloo.ca (Lennart Sorensen) Cc: torvalds@linux-foundation.org, tytso@mit.edu, drees76@gmail.com, jesper@krogh.cc, linux-kernel@vger.kernel.org Subject: Re: Linux 2.6.29 Message-Id: <20090401143622.b1885643.akpm@linux-foundation.org> In-Reply-To: <20090401210337.GB3797@csclub.uwaterloo.ca> References: <72dbd3150903241200v38720ca0x392c381f295bdea@mail.gmail.com> <20090325183011.GN32307@mit.edu> <20090325220530.GR32307@mit.edu> <20090326171148.9bf8f1ec.akpm@linux-foundation.org> <20090326174704.cd36bf7b.akpm@linux-foundation.org> <20090326182519.d576d703.akpm@linux-foundation.org> <20090401210337.GB3797@csclub.uwaterloo.ca> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1358 Lines: 31 On Wed, 1 Apr 2009 17:03:38 -0400 lsorense@csclub.uwaterloo.ca (Lennart Sorensen) wrote: > On Thu, Mar 26, 2009 at 06:25:19PM -0700, Andrew Morton wrote: > > The JBD journal is a massive designed-in contention point. It's why > > for several years I've been telling anyone who will listen that we need > > a new fs. Hopefully our response to all these problems will soon be > > "did you try btrfs?". > > Oh I look forward to the day when it will be safe to convert my mythtv > box from ext3 to btrfs. Current kernels just have too much IO latency > with ext3 it seems. Older kernels were more responsive, but probably > had other places they were less efficient. Back in 2002ish I did a *lot* of work on IO latency, reads-vs-writes, etc, etc (but not fsync - for practical purposes it's unfixable on ext3-ordered) Performance was pretty good. From some of the descriptions I'm seeing get tossed around lately, I suspect that it has regressed. It would be useful/interesting if people were to rerun some of these tests with `echo anticipatory > /sys/block/sda/queue/scheduler'. Or with linux-2.5.60 :( -- 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/