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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,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 873D4C432BE for ; Tue, 31 Aug 2021 09:23:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 64CAC606A5 for ; Tue, 31 Aug 2021 09:23:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240577AbhHaJYA (ORCPT ); Tue, 31 Aug 2021 05:24:00 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:48986 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239716AbhHaJX7 (ORCPT ); Tue, 31 Aug 2021 05:23:59 -0400 Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (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-out1.suse.de (Postfix) with ESMTPS id 35D952218C; Tue, 31 Aug 2021 09:23:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1630401783; 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=KEjheK3h00K+lY9OU2qNX5OkzKIkBPjT18RnPLeOtvw=; b=XsYZ+3djmOGV2B64OFpTbqfeJfg3PWodIWAcKOYMjjrWtHXl07rKXOWzcZISSP9ILtEmZr JN3ha3QJ/oMAxygs6zbKFpnDFf6sIjPe9zKOJSMdvN5cUQrPQ9Ar9l/SZXDFUgea5VGUK0 XbTzBy+PNAOBsEysYVJ+LzeFEYB8w74= Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (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 imap1.suse-dmz.suse.de (Postfix) with ESMTPS id 0983C139A3; Tue, 31 Aug 2021 09:23:03 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap1.suse-dmz.suse.de with ESMTPSA id T8ubAff0LWH9awAAGKfGzw (envelope-from ); Tue, 31 Aug 2021 09:23:03 +0000 Date: Tue, 31 Aug 2021 11:23:04 +0200 From: Michal =?iso-8859-1?Q?Koutn=FD?= To: Feng Tang Cc: Johannes Weiner , Linus Torvalds , andi.kleen@intel.com, kernel test robot , Roman Gushchin , Michal Hocko , Shakeel Butt , Balbir Singh , Tejun Heo , Andrew Morton , LKML , lkp@lists.01.org, kernel test robot , "Huang, Ying" , Zhengjun Xing Subject: Re: [mm] 2d146aa3aa: vm-scalability.throughput -36.4% regression Message-ID: <20210831092304.GA17119@blackbody.suse.cz> References: <20210811031734.GA5193@xsang-OptiPlex-9020> <20210812031910.GA63920@shbuild999.sh.intel.com> <20210816032855.GB72770@shbuild999.sh.intel.com> <20210817024500.GC72770@shbuild999.sh.intel.com> <20210817164737.GA23342@blackbody.suse.cz> <20210818023004.GA17956@shbuild999.sh.intel.com> <20210831063036.GA46357@shbuild999.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210831063036.GA46357@shbuild999.sh.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 31, 2021 at 02:30:36PM +0800, Feng Tang wrote: > Yes, I tried many re-arrangement of the members of cgroup_subsys_state, > and even close members of memcg, but there were no obvious changes. > What can recover the regresion is adding 128 bytes padding in the css, > no matter at the start, end or in the middle. Do you mean the padding added outside the .cgroup--.refcnt members area also restores the benchmark results? (Or you refer to paddings that move .cgroup and .refcnt across a cacheline border ?) I'm asking to be sure we have correct understanding of what members are contended (what's the frequent writer). Thanks, Michal