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=-0.9 required=3.0 tests=FROM_EXCESS_BASE64, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,UNPARSEABLE_RELAY autolearn=unavailable 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 1B558C282E1 for ; Tue, 23 Apr 2019 09:14:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6F3320843 for ; Tue, 23 Apr 2019 09:14:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727031AbfDWJO5 (ORCPT ); Tue, 23 Apr 2019 05:14:57 -0400 Received: from out30-44.freemail.mail.aliyun.com ([115.124.30.44]:40015 "EHLO out30-44.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725888AbfDWJO5 (ORCPT ); Tue, 23 Apr 2019 05:14:57 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R821e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04446;MF=yun.wang@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0TQ1rXBG_1556010893; Received: from testdeMacBook-Pro.local(mailfrom:yun.wang@linux.alibaba.com fp:SMTPD_---0TQ1rXBG_1556010893) by smtp.aliyun-inc.com(127.0.0.1); Tue, 23 Apr 2019 17:14:53 +0800 Subject: Re: [RFC PATCH 1/5] numa: introduce per-cgroup numa balancing locality, statistic To: Peter Zijlstra Cc: hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com, Ingo Molnar , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <209d247e-c1b2-3235-2722-dd7c1f896483@linux.alibaba.com> <20190423084444.GB11158@hirez.programming.kicks-ass.net> From: =?UTF-8?B?546L6LSH?= Message-ID: Date: Tue, 23 Apr 2019 17:14:53 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190423084444.GB11158@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/4/23 δΈ‹εˆ4:44, Peter Zijlstra wrote: > On Mon, Apr 22, 2019 at 10:11:24AM +0800, ηŽ‹θ΄‡ wrote: >> +#ifdef CONFIG_NUMA_BALANCING >> + >> +enum memcg_numa_locality_interval { >> + PERCENT_0_9, >> + PERCENT_10_19, >> + PERCENT_20_29, >> + PERCENT_30_39, >> + PERCENT_40_49, >> + PERCENT_50_59, >> + PERCENT_60_69, >> + PERCENT_70_79, >> + PERCENT_80_89, >> + PERCENT_90_100, >> + NR_NL_INTERVAL, >> +}; >> + >> +struct memcg_stat_numa { >> + u64 locality[NR_NL_INTERVAL]; >> +}; > If you make that 8 it fits a single cacheline. Do you really need the > additional resolution? If so, then 16 would be the next logical amount > of buckets. 10 otoh makes no sense what so ever. Thanks for point out :-) not have to be 10, I think we can save first two and make it PERCENT_0_29, already wrong enough if it drops below 30% and it's helpless to know detail changes in this section. Regards, Michael Wang >