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,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,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 A9FF0C433B4 for ; Thu, 15 Apr 2021 17:41:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86FA5611AB for ; Thu, 15 Apr 2021 17:41:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234188AbhDORlg (ORCPT ); Thu, 15 Apr 2021 13:41:36 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:51503 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233980AbhDORlf (ORCPT ); Thu, 15 Apr 2021 13:41:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1618508471; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wTimRIr0YgBuVLpWvKPM6c0MAPH0f+KQspjahIIUAlU=; b=cPDV7WzTQ9rHwfUAQ/ac8bvWdvjyTkXGWriMaF++nEkSbJ+qL0n8Miec9j2pcwCP3jD+sH R6TckrEa6JX8ZyygS7AnxLHcSdnNw7s2A6J/GQ6S4KME/FKCJ9tWSLOBsC0ts8eb/9IbGh oJuCPBuWTEs8RtOWTWoY/1i4yja7kqQ= Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-596-pxp1gya3MFWwH2GlIlJCMA-1; Thu, 15 Apr 2021 13:41:10 -0400 X-MC-Unique: pxp1gya3MFWwH2GlIlJCMA-1 Received: by mail-qt1-f199.google.com with SMTP id e6-20020ac85dc60000b029019d9cbbc077so4492900qtx.11 for ; Thu, 15 Apr 2021 10:41:10 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:subject:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=wTimRIr0YgBuVLpWvKPM6c0MAPH0f+KQspjahIIUAlU=; b=Ve7bkuUc5dERHWidVXG+3JYCKnFzBVCDj018pj5qXNlC3nlL8dr8thzmq1cQe2HeBm EopzT+s/XNAOfeAzahPlPs9PeM81CfLKWWzUDuMGhBg4GpEsU5Y/zEEgn9LAcKB9WQKI plb1i7slkyf51Rc15ZfV8+SkTGk3ZCjuHtBMIIr/kXoQYy24/Zkhu2a/e6Jdh6mb+w/G +KMw4HITbLfVooZf6eKpPX2n9RVzZryDx8/Evbg83ICkQ3Tcjm2j0k5peb/zjSBdI+Nw G7AZ8mIwgKyT8SeCwQm5Fi/w7q1txzlz02nCe7u40mVq/fqycbP/ZC+8jXL6nQjtLQAu 9bqA== X-Gm-Message-State: AOAM531VeJbEISWjJ6sl4XW7vC9SHDxXfZA0HwT6k03aPlBGkmc1qrOH wl9eti5C1fV59dz0zLgg9mzv/m7LugYUXXcvAHppUcSUUeeRplBvBJ6fRG6y59fTWCFxUGIyUio L4DcYc7V5kLnpsmvnENiLJ1Sy X-Received: by 2002:a37:7c5:: with SMTP id 188mr4791832qkh.348.1618508469965; Thu, 15 Apr 2021 10:41:09 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzmgbFnszT76GybNyzgAt7zTaWK3t49+b+KRVvGIM0rKdDofO0Sm6ySwTeX6EQ7djs0OMFxww== X-Received: by 2002:a37:7c5:: with SMTP id 188mr4791794qkh.348.1618508469626; Thu, 15 Apr 2021 10:41:09 -0700 (PDT) Received: from llong.remote.csb ([2601:191:8500:76c0::cdbc]) by smtp.gmail.com with ESMTPSA id x18sm2247420qtj.58.2021.04.15.10.41.08 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 15 Apr 2021 10:41:09 -0700 (PDT) From: Waiman Long X-Google-Original-From: Waiman Long Subject: Re: [PATCH v3 0/5] mm/memcg: Reduce kmemcache memory accounting overhead To: Matthew Wilcox Cc: Johannes Weiner , Michal Hocko , Vladimir Davydov , Andrew Morton , Tejun Heo , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, Shakeel Butt , Muchun Song , Alex Shi , Chris Down , Yafang Shao , Wei Yang , Masayoshi Mizuma , Xing Zhengjun References: <20210414012027.5352-1-longman@redhat.com> <20210415171035.GB2531743@casper.infradead.org> Message-ID: <15cf3cfa-c221-9e84-9f5b-80082207efd3@redhat.com> Date: Thu, 15 Apr 2021 13:41:07 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: <20210415171035.GB2531743@casper.infradead.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/15/21 1:10 PM, Matthew Wilcox wrote: > On Tue, Apr 13, 2021 at 09:20:22PM -0400, Waiman Long wrote: >> With memory accounting disable, the run time was 2.848s. With memory >> accounting enabled, the run times with the application of various >> patches in the patchset were: >> >> Applied patches Run time Accounting overhead Overhead %age >> --------------- -------- ------------------- ------------- >> None 10.800s 7.952s 100.0% >> 1-2 9.140s 6.292s 79.1% >> 1-3 7.641s 4.793s 60.3% >> 1-5 6.801s 3.953s 49.7% > I think this is a misleading way to report the overhead. I would have said: > > 10.800s 7.952s 279.2% > 9.140s 6.292s 220.9% > 7.641s 4.793s 168.3% > 6.801s 3.953s 138.8% > What I want to emphasize is the reduction in the accounting overhead part of execution time. Your percentage used the accounting disable time as the denominator. I think both are valid, I will be more clear about that in my version of the patch. Thanks, Longman