From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E05BC35247 for ; Fri, 7 Feb 2020 01:10:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2EA3820715 for ; Fri, 7 Feb 2020 01:10:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727341AbgBGBKw (ORCPT ); Thu, 6 Feb 2020 20:10:52 -0500 Received: from out30-132.freemail.mail.aliyun.com ([115.124.30.132]:57142 "EHLO out30-132.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726956AbgBGBKw (ORCPT ); Thu, 6 Feb 2020 20:10:52 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R171e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e07488;MF=yun.wang@linux.alibaba.com;NM=1;PH=DS;RN=18;SR=0;TI=SMTPD_---0TpJ7uBF_1581037833; Received: from testdeMacBook-Pro.local(mailfrom:yun.wang@linux.alibaba.com fp:SMTPD_---0TpJ7uBF_1581037833) by smtp.aliyun-inc.com(127.0.0.1); Fri, 07 Feb 2020 09:10:46 +0800 Subject: Re: [PATCH v8 0/2] sched/numa: introduce numa locality From: =?UTF-8?B?546L6LSH?= To: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Luis Chamberlain , Kees Cook , Iurii Zaikin , =?UTF-8?Q?Michal_Koutn=c3=bd?= , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, "Paul E. McKenney" , Randy Dunlap , Jonathan Corbet References: <743eecad-9556-a241-546b-c8a66339840e@linux.alibaba.com> <207ef46c-672c-27c8-2012-735bd692a6de@linux.alibaba.com> <040def80-9c38-4bcc-e4a8-8a0d10f131ed@linux.alibaba.com> <25cf7ef5-e37e-7578-eea7-29ad0b76c4ea@linux.alibaba.com> <443641e7-f968-0954-5ff6-3b7e7fed0e83@linux.alibaba.com> Message-ID: <3b2c5a07-4bc0-1feb-2daf-260e4d58c7b6@linux.alibaba.com> Date: Fri, 7 Feb 2020 09:10:33 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Archived-At: List-Archive: List-Post: Hi, Peter, Ingo Could you give some comments please? As Mel replied previously, he won't disagree the idea, so we're looking forward the opinion from the maintainers. Please allow me to highlight the necessary of monitoring NUMA Balancing again, this feature is critical to the performance on NUMA platform, it cost and benefit -- lot or less, however there are not enough information for an admin to analysis the trade-off, while locality could be the missing piece. Regards, Michael Wang On 2020/1/21 上午9:56, 王贇 wrote: > v8: > * document edited > v7: > * rebased on latest linux-next > v6: > * fix compile failure when NUMA disabled > v5: > * improved documentation > v4: > * fix comments and improved documentation > v3: > * simplified the locality concept & implementation > v2: > * improved documentation > > Modern production environment could use hundreds of cgroup to control > the resources for different workloads, along with the complicated > resource binding. > > On NUMA platforms where we have multiple nodes, things become even more > complicated, we hope there are more local memory access to improve the > performance, and NUMA Balancing keep working hard to achieve that, > however, wrong memory policy or node binding could easily waste the > effort, result a lot of remote page accessing. > > We need to notice such problems, then we got chance to fix it before > there are too much damages, however, there are no good monitoring > approach yet to help catch the mouse who introduced the remote access. > > This patch set is trying to fill in the missing pieces， by introduce > the per-cgroup NUMA locality info, with this new statistics, we could > achieve the daily monitoring on NUMA efficiency, to give warning when > things going too wrong. > > Please check the second patch for more details. > > Michael Wang (2): > sched/numa: introduce per-cgroup NUMA locality info > sched/numa: documentation for per-cgroup numa statistics > > Documentation/admin-guide/cg-numa-stat.rst | 178 ++++++++++++++++++++++++ > Documentation/admin-guide/index.rst | 1 + > Documentation/admin-guide/kernel-parameters.txt | 4 + > Documentation/admin-guide/sysctl/kernel.rst | 9 ++ > include/linux/sched.h | 15 ++ > include/linux/sched/sysctl.h | 6 + > init/Kconfig | 11 ++ > kernel/sched/core.c | 75 ++++++++++ > kernel/sched/fair.c | 62 +++++++++ > kernel/sched/sched.h | 12 ++ > kernel/sysctl.c | 11 ++ > 11 files changed, 384 insertions(+) > create mode 100644 Documentation/admin-guide/cg-numa-stat.rst >