From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Goyal Subject: Re: [PATCH 15/20] io-controller: map async requests to appropriate cgroup Date: Mon, 22 Jun 2009 11:39:10 -0400 Message-ID: <20090622153910.GB15600@redhat.com> References: <1245443858-8487-1-git-send-email-vgoyal@redhat.com> <1245443858-8487-16-git-send-email-vgoyal@redhat.com> <4A3EE245.7030409@cn.fujitsu.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4A3EE245.7030409@cn.fujitsu.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Gui Jianfeng Cc: dhaval@linux.vnet.ibm.com, snitzer@redhat.com, peterz@infradead.org, dm-devel@redhat.com, dpshah@google.com, jens.axboe@oracle.com, agk@redhat.com, balbir@linux.vnet.ibm.com, paolo.valente@unimore.it, fernando@oss.ntt.co.jp, mikew@google.com, jmoyer@redhat.com, nauman@google.com, m-ikeda@ds.jp.nec.com, lizf@cn.fujitsu.com, fchecconi@gmail.com, akpm@linux-foundation.org, jbaron@redhat.com, linux-kernel@vger.kernel.org, s-uchida@ap.jp.nec.com, righi.andrea@gmail.com, containers@lists.linux-foundation.org List-Id: dm-devel.ids On Mon, Jun 22, 2009 at 09:45:41AM +0800, Gui Jianfeng wrote: > Vivek Goyal wrote: > > o So far we were assuming that a bio/rq belongs to the task who is submitting > > it. It did not hold good in case of async writes. This patch makes use of > > blkio_cgroup pataches to attribute the aysnc writes to right group instead > > of task submitting the bio. > > > > o For sync requests, we continue to assume that io belongs to the task > > submitting it. Only in case of async requests, we make use of io tracking > > patches to track the owner cgroup. > > > > o So far cfq always caches the async queue pointer. With async requests now > > not necessarily being tied to submitting task io context, caching the > > pointer will not help for async queues. This patch introduces a new config > > option CONFIG_TRACK_ASYNC_CONTEXT. If this option is not set, cfq retains > > old behavior where async queue pointer is cached in task context. If it > > is not set, async queue pointer is not cached and we take help of bio > > Here "If it is not set" should be "If it is set". Yes, in last line it should be "If it is set". Thanks Gui. Will fix the comment. Vivek From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757851AbZFVPk3 (ORCPT ); Mon, 22 Jun 2009 11:40:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750866AbZFVPkS (ORCPT ); Mon, 22 Jun 2009 11:40:18 -0400 Received: from mx2.redhat.com ([66.187.237.31]:55867 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753896AbZFVPkR (ORCPT ); Mon, 22 Jun 2009 11:40:17 -0400 Date: Mon, 22 Jun 2009 11:39:10 -0400 From: Vivek Goyal To: Gui Jianfeng Cc: linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org, dm-devel@redhat.com, jens.axboe@oracle.com, nauman@google.com, dpshah@google.com, lizf@cn.fujitsu.com, mikew@google.com, fchecconi@gmail.com, paolo.valente@unimore.it, ryov@valinux.co.jp, fernando@oss.ntt.co.jp, s-uchida@ap.jp.nec.com, taka@valinux.co.jp, jmoyer@redhat.com, dhaval@linux.vnet.ibm.com, balbir@linux.vnet.ibm.com, righi.andrea@gmail.com, m-ikeda@ds.jp.nec.com, jbaron@redhat.com, agk@redhat.com, snitzer@redhat.com, akpm@linux-foundation.org, peterz@infradead.org Subject: Re: [PATCH 15/20] io-controller: map async requests to appropriate cgroup Message-ID: <20090622153910.GB15600@redhat.com> References: <1245443858-8487-1-git-send-email-vgoyal@redhat.com> <1245443858-8487-16-git-send-email-vgoyal@redhat.com> <4A3EE245.7030409@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A3EE245.7030409@cn.fujitsu.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 22, 2009 at 09:45:41AM +0800, Gui Jianfeng wrote: > Vivek Goyal wrote: > > o So far we were assuming that a bio/rq belongs to the task who is submitting > > it. It did not hold good in case of async writes. This patch makes use of > > blkio_cgroup pataches to attribute the aysnc writes to right group instead > > of task submitting the bio. > > > > o For sync requests, we continue to assume that io belongs to the task > > submitting it. Only in case of async requests, we make use of io tracking > > patches to track the owner cgroup. > > > > o So far cfq always caches the async queue pointer. With async requests now > > not necessarily being tied to submitting task io context, caching the > > pointer will not help for async queues. This patch introduces a new config > > option CONFIG_TRACK_ASYNC_CONTEXT. If this option is not set, cfq retains > > old behavior where async queue pointer is cached in task context. If it > > is not set, async queue pointer is not cached and we take help of bio > > Here "If it is not set" should be "If it is set". Yes, in last line it should be "If it is set". Thanks Gui. Will fix the comment. Vivek