From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759801AbZDQJk4 (ORCPT ); Fri, 17 Apr 2009 05:40:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757524AbZDQJkr (ORCPT ); Fri, 17 Apr 2009 05:40:47 -0400 Received: from mail-fx0-f158.google.com ([209.85.220.158]:55654 "EHLO mail-fx0-f158.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754629AbZDQJkq (ORCPT ); Fri, 17 Apr 2009 05:40:46 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:mail-followup-to:references :mime-version:content-type:content-disposition:in-reply-to :user-agent; b=PsTvecJebPBDPansOJNkzWSjZEtXEqrPuAQfHI4G0eb+3qeXgKEydNuKkCtu82MLWj sQtR/iuh8uZVVzS0bKEFC8pMPj7MpGZmJyO9JgZQ9H4hxoQULaDEmpShlpljzl9TZSXK Qm3FTil6e97rfC1G9hgQbmfgspvntYVmbDVEA= Date: Fri, 17 Apr 2009 11:40:42 +0200 From: Andrea Righi To: Andrew Morton Cc: menage@google.com, balbir@linux.vnet.ibm.com, guijianfeng@cn.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, agk@sourceware.org, axboe@kernel.dk, baramsori72@gmail.com, chlunde@ping.uio.no, dave@linux.vnet.ibm.com, dpshah@google.com, eric.rannaud@gmail.com, fernando@oss.ntt.co.jp, taka@valinux.co.jp, lizf@cn.fujitsu.com, matt@bluehost.com, dradford@bluehost.com, ngupta@google.com, randy.dunlap@oracle.com, roberto@unbit.it, ryov@valinux.co.jp, s-uchida@ap.jp.nec.com, subrata@linux.vnet.ibm.com, yoshikawa.takuya@oss.ntt.co.jp, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/9] bio-cgroup controller Message-ID: <20090417094042.GB8689@linux> Mail-Followup-To: Andrew Morton , menage@google.com, balbir@linux.vnet.ibm.com, guijianfeng@cn.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com, agk@sourceware.org, axboe@kernel.dk, baramsori72@gmail.com, chlunde@ping.uio.no, dave@linux.vnet.ibm.com, dpshah@google.com, eric.rannaud@gmail.com, fernando@oss.ntt.co.jp, taka@valinux.co.jp, lizf@cn.fujitsu.com, matt@bluehost.com, dradford@bluehost.com, ngupta@google.com, randy.dunlap@oracle.com, roberto@unbit.it, ryov@valinux.co.jp, s-uchida@ap.jp.nec.com, subrata@linux.vnet.ibm.com, yoshikawa.takuya@oss.ntt.co.jp, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org References: <1239740480-28125-1-git-send-email-righi.andrea@gmail.com> <1239740480-28125-4-git-send-email-righi.andrea@gmail.com> <20090416152937.b2188370.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090416152937.b2188370.akpm@linux-foundation.org> 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 Thu, Apr 16, 2009 at 03:29:37PM -0700, Andrew Morton wrote: > On Tue, 14 Apr 2009 22:21:14 +0200 > Andrea Righi wrote: > > > Subject: [PATCH 3/9] bio-cgroup controller > > Sorry, but I have to register extreme distress at the name of this. > The term "bio" is well-established in the kernel and here we have a new > definition for the same term: "block I/O". > > "bio" was a fine term for you to have chosen from the user's > perspective, but from the kernel developer perspective it is quite > horrid. The patch adds a vast number of new symbols all into the > existing "bio_" namespace, many of which aren't related to `struct bio' > at all. > > At least, I think that's what's happening. Perhaps the controller > really _is_ designed to track `struct bio'? If so, that's an odd thing > to tell userspace about. > > > > The controller bio-cgroup is used by io-throttle to track writeback IO > > and for properly apply throttling. > > Presumably it tracks all forms of block-based I/O and not just delayed > writeback. For the general case bio-cgroup tracks all forms of block IO, in this particular case (only for the io-throttle controller) I used bio-cgroup to track writeback IO. Synchronous IO is accounted directly in submit_bio() and throttled as well, imposing explicit sleeps via schedule_timeout_killable(). -Andrea