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 1A573C433F5 for ; Fri, 25 Feb 2022 20:47:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6CC1C8D0002; Fri, 25 Feb 2022 15:47:24 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 654848D0001; Fri, 25 Feb 2022 15:47:24 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4F4E38D0002; Fri, 25 Feb 2022 15:47:24 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.25]) by kanga.kvack.org (Postfix) with ESMTP id 3C7568D0001 for ; Fri, 25 Feb 2022 15:47:24 -0500 (EST) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id F41F12AAD for ; Fri, 25 Feb 2022 20:47:23 +0000 (UTC) X-FDA: 79182487608.09.5A7EFC9 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf18.hostedemail.com (Postfix) with ESMTP id B5B361C00B7 for ; Fri, 25 Feb 2022 20:46:42 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id EC1B21F388; Fri, 25 Feb 2022 18:03:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1645812227; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=BeA/jlPuPW2P7IYhYhxCoCbYQRT74b/2eYzeIUlIjaI=; b=Ynl4p1xwVznCgB4IxQyr1B5bqNjdZKs6Uawz4aAguaJu/DffItocZjUcblswGAJPtHX6JS 2Ik5yWXuDAT7gL7a9xYYdzeF+zCxtCZIHMSmZ3kbCVK0GTy/AuFWsEPILF1X2Za+5IwX5n h5zCTSG/99XkAjj39qZvF3fIZAI0X2g= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id C28E113C17; Fri, 25 Feb 2022 18:03:47 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 9qDkLgMaGWKMRQAAMHmgww (envelope-from ); Fri, 25 Feb 2022 18:03:47 +0000 Date: Fri, 25 Feb 2022 19:03:45 +0100 From: Michal =?iso-8859-1?Q?Koutn=FD?= To: Ivan Babrou Cc: Daniel Dao , Shakeel Butt , kernel-team , Linux MM , Johannes Weiner , Roman Gushchin , Feng Tang , Michal Hocko , Hillf Danton , Andrew Morton , Linus Torvalds Subject: Re: Regression in workingset_refault latency on 5.15 Message-ID: <20220225180345.GD12037@blackbody.suse.cz> References: <20220224165838.oir5clpkkqpstpx3@google.com> <20220224185236.qgzm3jpoz2orjfcw@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=suse.com header.s=susede1 header.b=Ynl4p1xw; spf=pass (imf18.hostedemail.com: domain of mkoutny@suse.com designates 195.135.220.29 as permitted sender) smtp.mailfrom=mkoutny@suse.com; dmarc=pass (policy=quarantine) header.from=suse.com X-Rspamd-Server: rspam02 X-Rspam-User: X-Rspamd-Queue-Id: B5B361C00B7 X-Stat-Signature: j94ob9osc3xw138ss1yd68qbc9g4awcy X-HE-Tag: 1645822002-316306 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 Fri, Feb 25, 2022 at 09:08:50AM -0800, Ivan Babrou wrote: > This seems like a great first step that should be merged on its own. > It would be good to also do something to improve the CPU time spent in > delayed work, if possible, as 0.5% of on-CPU time is not a negligible > amount. BTW how many levels deep is the affected memory cgroup hierarchy (where the workingset_refault happens)? (Self answer: Probably less than nr_cpus*MEMCG_BATCH, so not relevant.) Thanks, Michal