Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765439AbZDBQac (ORCPT ); Thu, 2 Apr 2009 12:30:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755593AbZDBQaS (ORCPT ); Thu, 2 Apr 2009 12:30:18 -0400 Received: from qw-out-2122.google.com ([74.125.92.26]:4249 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755591AbZDBQaQ (ORCPT ); Thu, 2 Apr 2009 12:30:16 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=Ct84/DkngUzI5E61V+1hGYKsBIGC4ttgPHlxgLtNvgGHYsoj8/UjKWN2NKuiAy1s0w Y1k4LFaTgNgKzcRXpsVRAYQaivQVoadfK/K5PZasrv2TcHsiB7jiNX/9QIPudVxo7iN+ qgRMIIssPlIaGx+6T22hhLPICtGDNt5Csl6ds= MIME-Version: 1.0 In-Reply-To: <20090402110532.GA5132@aniel> References: <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> <20090402110532.GA5132@aniel> Date: Thu, 2 Apr 2009 09:29:59 -0700 Message-ID: <72dbd3150904020929w46c6dc0bs4028c49dd8fa8c56@mail.gmail.com> Subject: Re: Linux 2.6.29 From: David Rees To: Janne Grunau Cc: Lennart Sorensen , Andrew Morton , Linus Torvalds , Theodore Tso , Jesper Krogh , Linux Kernel Mailing List Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 914 Lines: 20 On Thu, Apr 2, 2009 at 4:05 AM, Janne Grunau wrote: >> Current kernels just have too much IO latency >> with ext3 it seems. > > MythTV calls fsync every few seconds on ongoing recordings to prevent > stalls due to large cache writebacks on ext3. Personally that is also one of my MythTV pet peeves. A hack added to MythTV to work around a crappy ext3 latency bug that also causes these large files to get heavily fragmented. That and the fact that yo have to patch MythTV to eliminate those forced fdatasyncs - there is no knob to turn it off if you're running MythTV on a filesystem which doesn't suffer from ext3's data=ordered fsync stalls. -Dave -- 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/