From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757540AbZDQBzy (ORCPT ); Thu, 16 Apr 2009 21:55:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753226AbZDQBzp (ORCPT ); Thu, 16 Apr 2009 21:55:45 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:59966 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753132AbZDQBzp (ORCPT ); Thu, 16 Apr 2009 21:55:45 -0400 Message-ID: <49E7E1CF.6060209@cn.fujitsu.com> Date: Fri, 17 Apr 2009 09:56:31 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: KAMEZAWA Hiroyuki CC: Andrea Righi , Paul Menage , Balbir Singh , Gui Jianfeng , agk@sourceware.org, akpm@linux-foundation.org, axboe@kernel.dk, baramsori72@gmail.com, Carl Henrik Lunde , dave@linux.vnet.ibm.com, Divyesh Shah , eric.rannaud@gmail.com, fernando@oss.ntt.co.jp, Hirokazu Takahashi , matt@bluehost.com, dradford@bluehost.com, ngupta@google.com, randy.dunlap@oracle.com, roberto@unbit.it, Ryo Tsuruta , Satoshi UCHIDA , subrata@linux.vnet.ibm.com, yoshikawa.takuya@oss.ntt.co.jp, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/9] io-throttle documentation References: <1239740480-28125-1-git-send-email-righi.andrea@gmail.com> <1239740480-28125-2-git-send-email-righi.andrea@gmail.com> <20090417102417.88a0ef93.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20090417102417.88a0ef93.kamezawa.hiroyu@jp.fujitsu.com> 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 KAMEZAWA Hiroyuki wrote: > On Tue, 14 Apr 2009 22:21:12 +0200 > Andrea Righi wrote: > >> +Example: >> +* Create an association between an io-throttle group and a bio-cgroup group >> + with "bio" and "blockio" subsystems mounted in different mount points: >> + # mount -t cgroup -o bio bio-cgroup /mnt/bio-cgroup/ >> + # cd /mnt/bio-cgroup/ >> + # mkdir bio-grp >> + # cat bio-grp/bio.id >> + 1 >> + # mount -t cgroup -o blockio blockio /mnt/io-throttle >> + # cd /mnt/io-throttle >> + # mkdir foo >> + # echo 1 > foo/blockio.bio_id > > Why do we need multiple cgroups at once to track I/O ? > Seems complicated to me. > IIUC, it also disallows other subsystems to be binded with blockio subsys: # mount -t cgroup -o blockio cpuset xxx /mnt (failed) and if a task is moved from cg1(id=1) to cg2(id=2) in bio subsys, this task will be moved from CG1(id=1) to CG2(id=2) automatically in blockio subsys. All these are odd, unexpected, complex and bug-prone I think..