From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753930Ab3GIM5l (ORCPT ); Tue, 9 Jul 2013 08:57:41 -0400 Received: from mail-pa0-f50.google.com ([209.85.220.50]:49532 "EHLO mail-pa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752690Ab3GIM5h (ORCPT ); Tue, 9 Jul 2013 08:57:37 -0400 Date: Tue, 9 Jul 2013 05:57:34 -0700 From: Tejun Heo To: Konstantin Khlebnikov Cc: Vivek Goyal , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , cgroups@vger.kernel.org, Andrew Morton , Sha Zhengju , devel@openvz.org, Jens Axboe Subject: Re: [PATCH RFC] fsio: filesystem io accounting cgroup Message-ID: <20130709125734.GA2478@htj.dyndns.org> References: <20130708100046.14417.12932.stgit@zurg> <20130708170047.GA18600@mtj.dyndns.org> <20130708175201.GB9094@redhat.com> <20130708175607.GB18600@mtj.dyndns.org> <51DBC99F.4030301@openvz.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51DBC99F.4030301@openvz.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tue, Jul 09, 2013 at 12:28:15PM +0400, Konstantin Khlebnikov wrote: > Yep, blkio has plenty problems and flaws and I don't get how it's related > to vfs layer, dirty set control and non-disk or network backed filesystems. > Any problem can be fixed by introducing new abstract layer, except too many > abstraction levels. Cgroup is pluggable subsystem, blkio has it's own plugins > and it's build on top of io scheduler plugin. All this stuff always have worked What does that have to do with anything? > with block devices. Now you suggest to handle all filesystems in this stack. > I think binding them to unrealated cgroup is rough leveling violation. How is blkio unrelated to filesystems mounted on block devices? You're suggesting a duplicate solution which can't be complete. > NFS cannot be controlled only by network throttlers because we > cannot slow down writeback process when it happens, we must slow > down tasks who generates dirty memory. That's exactly the same problem why blkio doesn't work for async IOs right now, so if you're interested in the area, please contribute to fixing that problem. > Plus it's close to impossible to separate several workloads if they > share one NFS sb. Again, the same problem with blkio. We need separate pressure channels on bdi for each cgroup. Thanks. -- tejun