From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: Re: cgroup: status-quo and userland efforts Date: Mon, 8 Apr 2013 17:46:09 +0400 Message-ID: <5162CA21.4060108@parallels.com> References: <20130406012159.GA17159@mtj.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130406012159.GA17159-9pTldWuhBndy/B6EtB590w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Tejun Heo Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Kay Sievers , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, lpoetter-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, jpoimboe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dhaval.giani-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, workman-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: containers.vger.kernel.org On 04/06/2013 05:21 AM, Tejun Heo wrote: > Hello, guys. > Hello Tejun, how are you? > Status-quo > ========== > tl;did read; This is mostly sensible. There is still one problem that we hadn't yet had the bandwidth to tackle that should be added to your official TODO list. The cpu cgroup needs a real-time timeslice to accept real time tasks. It defaults to 0, meaning that a newly created cpu cgroup cannot accept tasks (rt tasks) without the user having to manually configure it. As far as I know, this problem hasn't yet been fixed. The fix of course, is as trivial as setting a new value instead of 0 as a default. The complication lies in determining which value should that be. There are many things that we should ask from a controller to implement in order to be able to handle fully joint hierarchies. One of them, IMHO, is that if you drop a task into a newly created cgroup it should run without the user having to do anything for it. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935998Ab3DHNpd (ORCPT ); Mon, 8 Apr 2013 09:45:33 -0400 Received: from mx2.parallels.com ([199.115.105.18]:36382 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934619Ab3DHNpb (ORCPT ); Mon, 8 Apr 2013 09:45:31 -0400 Message-ID: <5162CA21.4060108@parallels.com> Date: Mon, 8 Apr 2013 17:46:09 +0400 From: Glauber Costa User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130311 Thunderbird/17.0.4 MIME-Version: 1.0 To: Tejun Heo CC: Li Zefan , , , Kay Sievers , , , , , Subject: Re: cgroup: status-quo and userland efforts References: <20130406012159.GA17159@mtj.dyndns.org> In-Reply-To: <20130406012159.GA17159@mtj.dyndns.org> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/06/2013 05:21 AM, Tejun Heo wrote: > Hello, guys. > Hello Tejun, how are you? > Status-quo > ========== > tl;did read; This is mostly sensible. There is still one problem that we hadn't yet had the bandwidth to tackle that should be added to your official TODO list. The cpu cgroup needs a real-time timeslice to accept real time tasks. It defaults to 0, meaning that a newly created cpu cgroup cannot accept tasks (rt tasks) without the user having to manually configure it. As far as I know, this problem hasn't yet been fixed. The fix of course, is as trivial as setting a new value instead of 0 as a default. The complication lies in determining which value should that be. There are many things that we should ask from a controller to implement in order to be able to handle fully joint hierarchies. One of them, IMHO, is that if you drop a task into a newly created cgroup it should run without the user having to do anything for it.