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=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=ham 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 B2DBFC3A5A1 for ; Thu, 22 Aug 2019 11:57:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8F51E233FC for ; Thu, 22 Aug 2019 11:57:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733240AbfHVL5D (ORCPT ); Thu, 22 Aug 2019 07:57:03 -0400 Received: from out30-131.freemail.mail.aliyun.com ([115.124.30.131]:34132 "EHLO out30-131.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731156AbfHVL5C (ORCPT ); Thu, 22 Aug 2019 07:57:02 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R101e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04426;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0Ta8EzwU_1566475019; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0Ta8EzwU_1566475019) by smtp.aliyun-inc.com(127.0.0.1); Thu, 22 Aug 2019 19:56:59 +0800 Subject: Re: [PATCH 00/14] per memcg lru_lock To: Daniel Jordan , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Mel Gorman , Tejun Heo , Michal Hocko References: <1566294517-86418-1-git-send-email-alex.shi@linux.alibaba.com> <6ba1ffb0-fce0-c590-c373-7cbc516dbebd@oracle.com> From: Alex Shi Message-ID: <348495d2-b558-fdfd-a411-89c75d4a9c78@linux.alibaba.com> Date: Thu, 22 Aug 2019 19:56:59 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <6ba1ffb0-fce0-c590-c373-7cbc516dbebd@oracle.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2019/8/22 上午2:00, Daniel Jordan 写道: >> > > This is system-wide right, not per container?  Even per container, 89 usec isn't much contention over 20 seconds.  You may want to give this a try: yes, perf lock show the host info. > >   https://git.kernel.org/pub/scm/linux/kernel/git/wfg/vm-scalability.git/tree/case-lru-file-readtwice> > It's also synthetic but it stresses lru_lock more than just anon alloc/free.  It hits the page activate path, which is where we see this lock in our database, and if enough memory is configured lru_lock also gets stressed during reclaim, similar to [1]. Thanks for the sharing, this patchset can not help the [1] case, since it's just relief the per container lock contention now. Yes, readtwice case could be more sensitive for this lru_lock changes in containers. I may try to use it in container with some tuning. But anyway, aim9 is also pretty good to show the problem and solutions. :) > > It'd be better though, as Michal suggests, to use the real workload that's causing problems.  Where are you seeing contention? We repeatly create or delete a lot of different containers according to servers load/usage, so normal workload could cause lots of pages alloc/remove. aim9 could reflect part of scenarios. I don't know the DB scenario yet. > >> With this patch series, lruvec->lru_lock show no contentions >>          &(&lruvec->lru_l...          8          0               0       0               0               0 >> >> and aim9 page_test/brk_test performance increased 5%~50%. > > Where does the 50% number come in?  The numbers below seem to only show ~4% boost. the Setddev/CoeffVar case has about 50% performance increase. one of container's mmtests result as following: Stddev page_test 245.15 ( 0.00%) 189.29 ( 22.79%) Stddev brk_test 1258.60 ( 0.00%) 629.16 ( 50.01%) CoeffVar page_test 0.71 ( 0.00%) 0.53 ( 26.05%) CoeffVar brk_test 1.32 ( 0.00%) 0.64 ( 51.14%)