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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8698FC433EF for ; Tue, 14 Dec 2021 05:49:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id F3F146B0071; Tue, 14 Dec 2021 00:49:30 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id EEE046B0072; Tue, 14 Dec 2021 00:49:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DDC986B0074; Tue, 14 Dec 2021 00:49:30 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0239.hostedemail.com [216.40.44.239]) by kanga.kvack.org (Postfix) with ESMTP id CEC5B6B0071 for ; Tue, 14 Dec 2021 00:49:30 -0500 (EST) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 8A336884BC for ; Tue, 14 Dec 2021 05:49:20 +0000 (UTC) X-FDA: 78915322080.26.74353D1 Received: from mail-pf1-f175.google.com (mail-pf1-f175.google.com [209.85.210.175]) by imf05.hostedemail.com (Postfix) with ESMTP id 0C146100002 for ; Tue, 14 Dec 2021 05:49:19 +0000 (UTC) Received: by mail-pf1-f175.google.com with SMTP id x131so16895063pfc.12 for ; Mon, 13 Dec 2021 21:49:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=hr5Wpg7ev5riau6J8AsCFp781PoK7TjuAKB0LRsYr3M=; b=MGzriN/1d6rVkfghphGHEsPbps/B1r5OA9eMGSvm2IKrjCXb0PzoKrJDOzPDS7VoHB +Dm8hdW4+kc1yTvSiKAs8t5CxMYVHJfvvEWl9iYvT4WOYrnSVZQQbJuWSusCeAkFMbhj RyVNEnjVkS04PRGrKG0B6F8eiI63e6Mcrdnc5sePETXwcY0fRexAovoxestlOy9lKSty ST7EC1CsMlXkgu2mD6xavaP2X1vIApimw+TabhmqiQDEBsBesiZoeN3EG5kCQ3SNA8/d uDAiabvJF5LOP5OR1SzEvHDWQpPTmLP6LII/jI4pG1z0mPvt4q60SEC/38UQWW2lX6Dc KBSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=hr5Wpg7ev5riau6J8AsCFp781PoK7TjuAKB0LRsYr3M=; b=znCFee+P/HtqSvdyy0iGjj8sh4fCvAfQAPeDOO/ZywLb/YaryRaD9SFgnijN+GbcP8 9cBzAlLmD7PHpQSC07/BPWJ9Q2phjniZOrNSo8l7WwnEVc+J5HtYt/uxdkucy757TShM j9OZwdf5zM+L6SreG2VaxFePEEcRaDKM6fTO67xCIAryPQlJ262CC7+AJnT6JrJ//nYr 4gaPQxltuPgfC6UcafD68uf8gL7nMb6JbzWKR0wx3DWDbc6UndUqqCoHlldtwFe9KSr1 pwbQ3+XGshzfLfY6+Pq3liQuhfju7UghZH5ukUu/yXSqSxhBWGBZCGgoxnSfyrvc0plz KKpQ== X-Gm-Message-State: AOAM531nlIAARnL2arK5O4594i9fZ8SUVkXw0UaPByZqTdLobBwQMpPb 8s2G/AJyZKn+BlKxIfUKJGQ= X-Google-Smtp-Source: ABdhPJwtcjX0i478P/HBWMUvhwLpZphrfwuE0Nb6BbP6+qiPvYmFDBBXmpwdnT2nBbQBfhimLlIQwA== X-Received: by 2002:a05:6a00:99e:b0:49f:f9e2:c116 with SMTP id u30-20020a056a00099e00b0049ff9e2c116mr2441444pfg.83.1639460958872; Mon, 13 Dec 2021 21:49:18 -0800 (PST) Received: from localhost ([110.141.142.237]) by smtp.gmail.com with ESMTPSA id z13sm2005224pfj.160.2021.12.13.21.49.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Dec 2021 21:49:17 -0800 (PST) Date: Tue, 14 Dec 2021 16:49:14 +1100 From: Balbir Singh To: yong w Cc: Andrew Morton , "Peter Zijlstra (Intel)" , mingo@kernel.org, LKML , Linux MM , yang.yang29@zte.com.cn, wang.yong12@zte.com.cn Subject: Re: [PATCH v2 linux-next] delayacct: track delays from memory compact Message-ID: References: <1638619795-71451-1-git-send-email-wang.yong12@zte.com.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 0C146100002 X-Stat-Signature: i6q19osw69p4x6ycx9g6dhw39q9um4up Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b="MGzriN/1"; spf=pass (imf05.hostedemail.com: domain of bsingharora@gmail.com designates 209.85.210.175 as permitted sender) smtp.mailfrom=bsingharora@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-HE-Tag: 1639460959-648104 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Dec 13, 2021 at 09:56:08PM +0800, yong w wrote: > Hello, is this patch OK? >=20 > Thanks. >=20 > yong w =E4=BA=8E2021=E5=B9=B412=E6=9C=888=E6=97=A5= =E5=91=A8=E4=B8=89 00:50=E5=86=99=E9=81=93=EF=BC=9A > > > > Balbir Singh =E4=BA=8E2021=E5=B9=B412=E6=9C=88= 7=E6=97=A5=E5=91=A8=E4=BA=8C 13:16=E5=86=99=E9=81=93=EF=BC=9A > > > > > > On Sun, Dec 05, 2021 at 07:08:02PM +0800, yong w wrote: > > > > Balbir Singh =E4=BA=8E2021=E5=B9=B412=E6=9C= =885=E6=97=A5=E5=91=A8=E6=97=A5 16:17=E5=86=99=E9=81=93=EF=BC=9A > > > > > > > > > > On Sat, Dec 04, 2021 at 04:09:55AM -0800, yongw.pur@gmail.com w= rote: > > > > > > From: wangyong > > > > > > > > > > > > Delay accounting does not track the delay of memory compact. > > > > > > When there is not enough free memory, tasks can spend > > > > > > a amount of their time waiting for compact. > > > > > > > > > > > > To get the impact of tasks in direct memory compact, measure > > > > > > the delay when allocating memory through memory compact. > > > > > > > > > > > > > > > > Should we call this DIRECT_COMPACT and through documentation > > > > > or name change imply that this won't work for kcompactd the > > > > > kernel thread - based on my reading of the patches. > > > > > > > > > Using DIRECT_COMPACT is a little redundant=EF=BC=8Cbecause the > > > > delayacct stats of delay accounting is specific to tasks, it has > > > > nothing to do with kcompactd, which is similar to the RECLAIM fie= ld. > > > > > > > > > > What would we expect when we call delayacct -p > > > to be output? > > If the slow path of memory allocation is invoked in the kcompacd proc= ess, > > there may be delays being recorded. > > > > > Don't feel to strongly, but it can be confusing that kcompactd > > > has spent no time in compact'ing? Not that delayacct is used for > > > kernel threads, but I am not sure if that use case exists today. > > Yes, delayacct does not restrict the process of obtaining information= =EF=BC=8C > > but kcompactd is used for compaction, the compact delay of > > kcompatd is not actually a delay.Maybe it can be added to the > > document later to make it clearer. > > > > Thanks for your reply! Please avoid top posting, when you say added later, I presume more patches for documentation are coming. I am OK with the patch in that case. Reviewed-by: Balbir Singh Balbir Singh