From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752042Ab0CQDSM (ORCPT ); Tue, 16 Mar 2010 23:18:12 -0400 Received: from mail-iw0-f176.google.com ([209.85.223.176]:37169 "EHLO mail-iw0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751335Ab0CQDSK (ORCPT ); Tue, 16 Mar 2010 23:18:10 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:subject:to:cc:in-reply-to:references; b=m0lX4wLYzBLErZOP/f8FZcTznhxX5ZDH8cG7nfMtSMHqmrQoqgl9d9nMf9AboAWQAx Wf+LSx4UTSJ2ppqP1Qnph9XYqK4bl+DusWRPyfk/UknE0ugvNGvzuh3WxPTA69DksRyD 4yrFSyhc4RUhOFwRHCOpy8MV22ndN4Bz0n/vQ= Message-ID: <4ba049f1.017ee70a.5ce6.1456@mx.google.com> Date: Tue, 16 Mar 2010 20:18:09 -0700 (PDT) From: Ben Gamari Subject: Re: Poor interactive performance with I/O loads with fsync()ing To: tytso@mit.edu Cc: linux-kernel@vger.kernel.org, Olly Betts , martin f krafft In-Reply-To: <20100317012439.GA8256@thunk.org> References: <4b9fa440.12135e0a.7fc8.ffffe745@mx.google.com> <20100317012439.GA8256@thunk.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sorry about the lack of any useful information in my initial email. I clearly didn't read it before sending. On Tue, 16 Mar 2010 21:24:39 -0400, tytso@mit.edu wrote: > What kernel version are you using; what distribution and what version > of that distro are you running; what file system are you using and > what if any mount options are you using? And what kind of hard drives > do you have? While this problem has been around for some time, my current configuration is the following: Kernel 2.6.32 (although also reproducible with kernels at least as early as 2.6.28) Filesystem: Now Btrfs (was ext4 less than a week ago), default mount options Hard drive: Seagate Momentus 7200.4 (ST9500420AS) Distribution: Ubuntu 9.10 (Karmic) > > I'm going to assume you're running into the standard ext3 > "data=ordered" entagled writes problem. There are solutions, such as > switching to using ext4, mounting with data=writeback mode, but they > have various shortcomings. > Unfortunately several people have continued to encounter unacceptable latency, even with ext4 and data=writeback. > A number of improvements have been made in ext3 and ext4 since some of > the discussions you quoted, but since you didn't tell us what > distribution version and/or what kernel version you are using, we > can't tell you are using those newer improvements yet. > Sorry about that. I should know better by now. - Ben