Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757298Ab1CISEk (ORCPT ); Wed, 9 Mar 2011 13:04:40 -0500 Received: from smtp-out.google.com ([216.239.44.51]:24299 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756306Ab1CISEi convert rfc822-to-8bit (ORCPT ); Wed, 9 Mar 2011 13:04:38 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=google.com; s=beta; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; b=KRf5mHYGAn7ZJ5abYwz1Xv1wluFald4mTJn0iEreTBJOO021Yrp6v0gTMafQJhlndL eilED1d/nJcASBDPbt4Q== MIME-Version: 1.0 In-Reply-To: <20110308225059.GL27455@redhat.com> References: <1299619256-12661-1-git-send-email-teravest@google.com> <20110308224325.GK27455@redhat.com> <20110308225059.GL27455@redhat.com> From: Justin TerAvest Date: Wed, 9 Mar 2011 10:04:11 -0800 Message-ID: Subject: Re: [RFC] [PATCH 0/6] Provide cgroup isolation for buffered writes. To: Vivek Goyal Cc: m-ikeda@ds.jp.nec.com, jaxboe@fusionio.com, linux-kernel@vger.kernel.org, ryov@valinux.co.jp, taka@valinux.co.jp, kamezawa.hiroyu@jp.fujitsu.com, righi.andrea@gmail.com, guijianfeng@cn.fujitsu.com, balbir@linux.vnet.ibm.com, ctalbott@google.com, nauman@google.com, mrubin@google.com Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4192 Lines: 94 On Tue, Mar 8, 2011 at 2:50 PM, Vivek Goyal wrote: > On Tue, Mar 08, 2011 at 05:43:25PM -0500, Vivek Goyal wrote: >> On Tue, Mar 08, 2011 at 01:20:50PM -0800, Justin TerAvest wrote: >> > This patchset adds tracking to the page_cgroup structure for which cgroup has >> > dirtied a page, and uses that information to provide isolation between >> > cgroups performing writeback. >> > >> >> Justin, >> >> So if somebody is trying to isolate a workload which does bunch of READS >> and lots of buffered WRITES, this patchset should help in the sense that >> all the heavy WRITES can be put into a separate cgroup of low weight? >> >> Other application which are primarily doing READS, direct WRITES or little >> bit of buffered WRITES should still get good latencies if heavy writer >> is isolated in a separate group? >> >> If yes, then this piece standalone can make sense. And once the other >> piece/patches of memory cgroup dirty ratio and cgroup aware buffered >> writeout come in, then one will be able to differentiate buffered writes >> of different groups. > > Thinking more about it, currently anyway SYNC preempts the ASYNC. So the > question would be will it help me enable get better isolation latencies > of READS agains buffered WRITES? Ah! Sorry, I left out a patch that disables cross-group preemption. I'll add that to the patchset and email out v2 soon. > > Thanks > Vivek > >> >> Thanks >> Vivek >> >> > I know that there is some discussion to remove request descriptor limits >> > entirely, but I included a patch to introduce per-cgroup limits to enable >> > this functionality. Without it, we didn't see much isolation improvement. >> > >> > I think most of this material has been discussed on lkml previously, this is >> > just another attempt to make a patchset that handles buffered writes for CFQ. >> > >> > There was a lot of previous discussion at: >> > ? http://thread.gmane.org/gmane.linux.kernel/1007922 >> > >> > Thanks to Andrea Righi, Kamezawa Hiroyuki, Munehiro Ikeda, Nauman Rafique, >> > and Vivek Goyal for work on previous versions of these patches. >> > >> > >> > ?Documentation/block/biodoc.txt | ? 10 + >> > ?block/blk-cgroup.c ? ? ? ? ? ? | ?204 +++++++++++++++++++++- >> > ?block/blk-cgroup.h ? ? ? ? ? ? | ? ?9 +- >> > ?block/blk-core.c ? ? ? ? ? ? ? | ?216 +++++++++++++++-------- >> > ?block/blk-settings.c ? ? ? ? ? | ? ?2 +- >> > ?block/blk-sysfs.c ? ? ? ? ? ? ?| ? 60 ++++--- >> > ?block/cfq-iosched.c ? ? ? ? ? ?| ?390 +++++++++++++++++++++++++++++++--------- >> > ?block/cfq.h ? ? ? ? ? ? ? ? ? ?| ? ?6 +- >> > ?block/elevator.c ? ? ? ? ? ? ? | ? 11 +- >> > ?fs/buffer.c ? ? ? ? ? ? ? ? ? ?| ? ?2 + >> > ?fs/direct-io.c ? ? ? ? ? ? ? ? | ? ?2 + >> > ?include/linux/blk_types.h ? ? ?| ? ?2 + >> > ?include/linux/blkdev.h ? ? ? ? | ? 81 ++++++++- >> > ?include/linux/blkio-track.h ? ?| ? 89 +++++++++ >> > ?include/linux/elevator.h ? ? ? | ? 14 ++- >> > ?include/linux/iocontext.h ? ? ?| ? ?1 + >> > ?include/linux/memcontrol.h ? ? | ? ?6 + >> > ?include/linux/mmzone.h ? ? ? ? | ? ?4 +- >> > ?include/linux/page_cgroup.h ? ?| ? 12 +- >> > ?init/Kconfig ? ? ? ? ? ? ? ? ? | ? 16 ++ >> > ?mm/Makefile ? ? ? ? ? ? ? ? ? ?| ? ?3 +- >> > ?mm/bounce.c ? ? ? ? ? ? ? ? ? ?| ? ?2 + >> > ?mm/filemap.c ? ? ? ? ? ? ? ? ? | ? ?2 + >> > ?mm/memcontrol.c ? ? ? ? ? ? ? ?| ? ?6 + >> > ?mm/memory.c ? ? ? ? ? ? ? ? ? ?| ? ?6 + >> > ?mm/page-writeback.c ? ? ? ? ? ?| ? 14 ++- >> > ?mm/page_cgroup.c ? ? ? ? ? ? ? | ? 29 ++- >> > ?mm/swap_state.c ? ? ? ? ? ? ? ?| ? ?2 + >> > ?28 files changed, 985 insertions(+), 216 deletions(-) >> > >> > [PATCH 1/6] Add IO cgroup tracking for buffered writes. >> > [PATCH 2/6] Make async queues per cgroup. >> > [PATCH 3/6] Modify CFQ to use IO tracking information. >> > [PATCH 4/6] With per-cgroup async, don't special case queues. >> > [PATCH 5/6] Add stat for per cgroup writeout done by flusher. >> > [PATCH 6/6] Per cgroup request descriptor counts > -- 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/