From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757192Ab0JUChW (ORCPT ); Wed, 20 Oct 2010 22:37:22 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:59508 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1757142Ab0JUChU (ORCPT ); Wed, 20 Oct 2010 22:37:20 -0400 Message-ID: <4CBFA772.7000702@cn.fujitsu.com> Date: Thu, 21 Oct 2010 10:37:38 +0800 From: Gui Jianfeng User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 To: Vivek Goyal , Jens Axboe CC: Nauman Rafique , Chad Talbott , Divyesh Shah , linux kernel mailing list , Gui Jianfeng Subject: [PATCH 4/4] blkio-cgroup: Documents for use_hierarchy interface References: <4CBFA64D.6050800@cn.fujitsu.com> In-Reply-To: <4CBFA64D.6050800@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Documents for use_hierarchy interface. Signed-off-by: Gui Jianfeng --- Documentation/cgroups/blkio-controller.txt | 21 +++++++++++++++++++++ 1 files changed, 21 insertions(+), 0 deletions(-) diff --git a/Documentation/cgroups/blkio-controller.txt b/Documentation/cgroups/blkio-controller.txt index d6da611..df6c938 100644 --- a/Documentation/cgroups/blkio-controller.txt +++ b/Documentation/cgroups/blkio-controller.txt @@ -15,6 +15,21 @@ one is throttling policy which can be used to specify upper IO rate limits on devices. This policy is implemented in generic block layer and can be used on leaf nodes as well as higher level logical devices like device mapper. +Currently, both hierarchical bandwidth division and flat bandwidth division are +supported. Consider the follow hierarchy: + + grp1 + / \ + grp2 grp3 + / \ + grp4 grp5 + +All groups have a same weight 500, and only grp3 grp4 and grp5 are contending +for IO bandwidth. If flat bandwidth division is in use, grp3 grp4 and grp5 will +share the same bandwidth, that is 33.3% for each. If hierarchical bandwidth +division is in use, grp4 and grp5 will get 25% of bandwidth for each, gpr3 +will get the reset 50%. + HOWTO ===== Proportional Weight division of bandwidth @@ -142,6 +157,12 @@ Proportional weight policy files dev weight 8:16 300 +- blkio.use_hierarchy + - If this interface is set, hierarchical bandwidth division is enabled. + Ohterwise, flat bandwidth division is enabled. Currently this + interface only shows up in root cgroup, and works in the case that + there're no child cgroups. + - blkio.time - disk time allocated to cgroup per device in milliseconds. First two fields specify the major and minor number of the device and -- 1.6.5.2