From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755334Ab2DEQjE (ORCPT ); Thu, 5 Apr 2012 12:39:04 -0400 Received: from mail-yw0-f46.google.com ([209.85.213.46]:39009 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753853Ab2DEQjB (ORCPT ); Thu, 5 Apr 2012 12:39:01 -0400 Date: Thu, 5 Apr 2012 09:38:54 -0700 From: Tejun Heo To: Vivek Goyal Cc: Fengguang Wu , Jan Kara , Jens Axboe , linux-mm@kvack.org, sjayaraman@suse.com, andrea@betterlinux.com, jmoyer@redhat.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, kamezawa.hiroyu@jp.fujitsu.com, lizefan@huawei.com, containers@lists.linux-foundation.org, cgroups@vger.kernel.org, ctalbott@google.com, rni@google.com, lsf@lists.linux-foundation.org Subject: Re: [RFC] writeback and cgroup Message-ID: <20120405163854.GE12854@google.com> References: <20120403183655.GA23106@dhcp-172-17-108-109.mtv.corp.google.com> <20120404145134.GC12676@redhat.com> <20120404184909.GB29686@dhcp-172-17-108-109.mtv.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120404184909.GB29686@dhcp-172-17-108-109.mtv.corp.google.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey, Vivek. On Wed, Apr 04, 2012 at 11:49:09AM -0700, Tejun Heo wrote: > > I am not sure what are you trying to say here. But primarily blk-throttle > > will throttle read and direct IO. Buffered writes will go to root cgroup > > which is typically unthrottled. > > Ooh, my bad then. Anyways, then the same applies to blk-throttle. > Our current implementation essentially collapses at the face of > write-heavy workload. I went through the code and couldn't find where blk-throttle is discriminating async IOs. Were you saying that blk-throttle currently doesn't throttle because those IOs aren't associated with the dirtying task? If so, note that it's different from cfq which explicitly assigns all async IOs when choosing cfqq even if we fix tagging. Thanks. -- tejun From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [RFC] writeback and cgroup Date: Thu, 5 Apr 2012 09:38:54 -0700 Message-ID: <20120405163854.GE12854@google.com> References: <20120403183655.GA23106@dhcp-172-17-108-109.mtv.corp.google.com> <20120404145134.GC12676@redhat.com> <20120404184909.GB29686@dhcp-172-17-108-109.mtv.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Fengguang Wu , Jan Kara , Jens Axboe , linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, sjayaraman-IBi9RG/b67k@public.gmane.org, andrea-oIIqvOZpAevzfdHfmsDf5w@public.gmane.org, jmoyer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org, lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ctalbott-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, rni-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, lsf-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Vivek Goyal Return-path: Content-Disposition: inline In-Reply-To: <20120404184909.GB29686-RcKxWJ4Cfj1J2suj2OqeGauc2jM2gXBXkQQo+JxHRPFibQn6LdNjmg@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org Hey, Vivek. On Wed, Apr 04, 2012 at 11:49:09AM -0700, Tejun Heo wrote: > > I am not sure what are you trying to say here. But primarily blk-throttle > > will throttle read and direct IO. Buffered writes will go to root cgroup > > which is typically unthrottled. > > Ooh, my bad then. Anyways, then the same applies to blk-throttle. > Our current implementation essentially collapses at the face of > write-heavy workload. I went through the code and couldn't find where blk-throttle is discriminating async IOs. Were you saying that blk-throttle currently doesn't throttle because those IOs aren't associated with the dirtying task? If so, note that it's different from cfq which explicitly assigns all async IOs when choosing cfqq even if we fix tagging. Thanks. -- tejun From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx101.postini.com [74.125.245.101]) by kanga.kvack.org (Postfix) with SMTP id 8CF166B004A for ; Thu, 5 Apr 2012 12:39:01 -0400 (EDT) Received: by yhr47 with SMTP id 47so1027956yhr.14 for ; Thu, 05 Apr 2012 09:39:00 -0700 (PDT) Date: Thu, 5 Apr 2012 09:38:54 -0700 From: Tejun Heo Subject: Re: [RFC] writeback and cgroup Message-ID: <20120405163854.GE12854@google.com> References: <20120403183655.GA23106@dhcp-172-17-108-109.mtv.corp.google.com> <20120404145134.GC12676@redhat.com> <20120404184909.GB29686@dhcp-172-17-108-109.mtv.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120404184909.GB29686@dhcp-172-17-108-109.mtv.corp.google.com> Sender: owner-linux-mm@kvack.org List-ID: To: Vivek Goyal Cc: Fengguang Wu , Jan Kara , Jens Axboe , linux-mm@kvack.org, sjayaraman@suse.com, andrea@betterlinux.com, jmoyer@redhat.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, kamezawa.hiroyu@jp.fujitsu.com, lizefan@huawei.com, containers@lists.linux-foundation.org, cgroups@vger.kernel.org, ctalbott@google.com, rni@google.com, lsf@lists.linux-foundation.org Hey, Vivek. On Wed, Apr 04, 2012 at 11:49:09AM -0700, Tejun Heo wrote: > > I am not sure what are you trying to say here. But primarily blk-throttle > > will throttle read and direct IO. Buffered writes will go to root cgroup > > which is typically unthrottled. > > Ooh, my bad then. Anyways, then the same applies to blk-throttle. > Our current implementation essentially collapses at the face of > write-heavy workload. I went through the code and couldn't find where blk-throttle is discriminating async IOs. Were you saying that blk-throttle currently doesn't throttle because those IOs aren't associated with the dirtying task? If so, note that it's different from cfq which explicitly assigns all async IOs when choosing cfqq even if we fix tagging. Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . 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