Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755345Ab0HCI0S (ORCPT ); Tue, 3 Aug 2010 04:26:18 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:49769 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753852Ab0HCI0M (ORCPT ); Tue, 3 Aug 2010 04:26:12 -0400 Message-ID: <4C57D3C7.2010509@cn.fujitsu.com> Date: Tue, 03 Aug 2010 16:31:03 +0800 From: Li Zefan User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1b3pre) Gecko/20090513 Fedora/3.0-2.3.beta2.fc11 Thunderbird/3.0b2 MIME-Version: 1.0 To: "Serge E. Hallyn" CC: linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org, Daniel Lezcano , "Eric W. Biederman" , Paul Menage , Jamal Hadi Salim , Andrew Morton Subject: Re: [PATCH 3/3] cgroup : remove the ns_cgroup References: <20100729195629.GA13378@hallyn.com> <20100729195812.GB19015@hallyn.com> In-Reply-To: <20100729195812.GB19015@hallyn.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2199 Lines: 45 Cc: Andrew Serge E. Hallyn wrote: > The ns_cgroup is an annoying cgroup at the namespace / cgroup frontier. > > For example, a single process can not handle a big amount of namespaces > without interacting with this cgroup and falling in an exponential creation > time due to the nested cgroup directory depth (eg. /cgroup//...//...). > > That was spotted when creating a single process using multiple network namespaces, > the objective was 4096 network namespaces, but at 820 netns, the creation time > was dramatically slow and the creation time for a namespace increased from 10msec > to 10sec. After five hours, the expected numbers of netns was not reached. > Without the ns_cgroup interaction, 4K netns are created after 2 minutes. > > In order to solve that, we have to mount the cgroup with all the subsystems > except the ns_cgroup, it's a little weird and hard to manage from an administration > pov because we have to know what are the cgroup available on the system and we > can't do a simple 'mount -t cgroup cgroup /cgroup'. > > With the previous patch which adds a 'clone_children' parameter to a cgroup, > we should be able to remove the ns_cgroup and manage manually the creation + > adding a task to the cgroup consistenly with the rest of the subsystems. > > This patch removes the ns_cgroup as suggested in the following thread: > > https://lists.linux-foundation.org/pipermail/containers/2009-June/018616.html > > The 'cgroup_clone' function is removed because it is no longer used. > > Changelog: Jul 29 (seh): remove references to ns_cgroup_clone(), fix up > some documentation, and remove CONFIG_CGROUP_NS references. > > Signed-off-by: Daniel Lezcano > Signed-off-by: Serge E. Hallyn > Cc: Eric W. Biederman > Cc: Paul Menage > Cc: Jamal Hadi Salim Reviewed-by: Li Zefan -- 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/