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=-12.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 C5FB5C433E1 for ; Fri, 14 Aug 2020 21:15:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9BBC220774 for ; Fri, 14 Aug 2020 21:15:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="bYyuaTEq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728179AbgHNVPV (ORCPT ); Fri, 14 Aug 2020 17:15:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728112AbgHNVPU (ORCPT ); Fri, 14 Aug 2020 17:15:20 -0400 Received: from mail-il1-x141.google.com (mail-il1-x141.google.com [IPv6:2607:f8b0:4864:20::141]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52E10C061385; Fri, 14 Aug 2020 14:15:20 -0700 (PDT) Received: by mail-il1-x141.google.com with SMTP id z3so9627747ilh.3; Fri, 14 Aug 2020 14:15:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=tJMVJBnaXmXqh981RH/h7+Q4BiQVvI3wCXGlTjz6EWg=; b=bYyuaTEqbGMUDbMQT1N3adh8ZXqau382QojThewnW//4qEz3eZ/zrAaDMQ2DyZdy5S zy3hUU8M7NHVx+aHkrthzP7rx9gfHneJI0nSdRH9Ckd5lxNps3aL683LKaDWNsKgnYZM Lt+XpG2yMuTdQt8MznPtkrXzYmYBSamAHiQN0gr/ZKTOQNhfnS7FBtOsdNBgsXegXw43 TAgtcMLOko7OxUnCkBxGuIogU9IzzqRw3UAHDFpS3HbUFvqlslWZEjTR+rnWF0tc8VNO 9PavoPblmc7OTQ7XIa/bqusD5Dw8UajLsvr3Pqjx3usFzgELflUYZN+4bZqMnmJRkg7f yYag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=tJMVJBnaXmXqh981RH/h7+Q4BiQVvI3wCXGlTjz6EWg=; b=opm6RX5H9nI0rguz6NcbkMk7fDJHH1BZBKC0gYzgWqYmN5BoA9GfiErCuca3rHzbt2 AUuJ7Ijx6lUZ5/4jj4FKhaeWEGku+AMZz0Yq+eQN6a8Y9WPC1Z9/IeYkFpQVUVYPgGeY /Pl1mYOBaZIpLyql62oSv8f2iz1yZk0yjU8oy38tCmnGFhn0KHvwYj0ZaYZC7aa6jnKc OXCl8MgFXX86M1+9sndJdJtIhyetQNoYBFpxe37Uazo5dJOGCTT/m8oAx6uw9A8dT9qc yeFtdfcp7P40U13erKX15Ei41Rwwu5a8mHh8gKwi4GU3hLWKhPFGSn6JTL6YiZEVqvWd KV2g== X-Gm-Message-State: AOAM532RP3naOoENAHAU0xj4CQlq8+ptA+dzYHu/cnNyUvJpZSUCiuy7 H8wIrzmCQ73CjoTi2Y1yhfDKTMrx/1el/zWJjs8= X-Google-Smtp-Source: ABdhPJwpZ1nVKkZq07Dopl2XjbctppDLsyq/CUWPrYJGlfkx7y1ewbsXQzHhTu2pyEZDnsMGq5XWLhh+TTzjZ6JEaKE= X-Received: by 2002:a05:6e02:143:: with SMTP id j3mr3694759ilr.97.1597439719638; Fri, 14 Aug 2020 14:15:19 -0700 (PDT) MIME-Version: 1.0 References: <20200813035100.13054.25671.stgit@localhost.localdomain> <20200813040232.13054.82417.stgit@localhost.localdomain> <6c072332-ff16-757d-99dd-b8fbae131a0c@linux.alibaba.com> In-Reply-To: From: Alexander Duyck Date: Fri, 14 Aug 2020 14:15:08 -0700 Message-ID: Subject: Re: [RFC PATCH 2/3] mm: Drop use of test_and_set_skip in favor of just setting skip To: Alex Shi Cc: Yang Shi , kbuild test robot , Rong Chen , Konstantin Khlebnikov , "Kirill A. Shutemov" , Hugh Dickins , LKML , Daniel Jordan , linux-mm , Shakeel Butt , Matthew Wilcox , Johannes Weiner , Tejun Heo , cgroups@vger.kernel.org, Andrew Morton , Wei Yang , Mel Gorman , Joonsoo Kim Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 14, 2020 at 7:24 AM Alexander Duyck wrote: > > On Fri, Aug 14, 2020 at 12:19 AM Alex Shi wr= ote: > > > > > > > > =E5=9C=A8 2020/8/13 =E4=B8=8B=E5=8D=8812:02, Alexander Duyck =E5=86=99= =E9=81=93: > > > > > > Since we have dropped the late abort case we can drop the code that w= as > > > clearing the LRU flag and calling page_put since the abort case will = now > > > not be holding a reference to a page. > > > > > > Signed-off-by: Alexander Duyck > > > > seems the case-lru-file-mmap-read case drop about 3% on this patch in a= rough testing. > > on my 80 core machine. > > I'm not sure how it could have that much impact on the performance > since the total effect would just be dropping what should be a > redundant test since we tested the skip bit before we took the LRU > bit, so we shouldn't need to test it again after. > > I finally got my test setup working last night. I'll have to do some > testing in my environment and I can start trying to see what is going > on. So I ran the case-lru-file-mmap-read a few times and I don't see how it is supposed to be testing the compaction code. It doesn't seem like compaction is running at least on my system as a result of the test script. I wonder if testing this code wouldn't be better done using something like thpscale from the mmtests(https://github.com/gormanm/mmtests)? It seems past changes to the compaction code were tested using that, and the config script for the test explains that it is designed specifically to stress the compaction code. I have the test up and running now and hope to collect results over the weekend. There is one change I will probably make to this patch and that is to place the new code that is setting skip_updated where the old code was calling test_and_set_skip_bit. By doing that we can avoid extra checks and it should help to reduce possible collisions when setting the skip bit in the pageblock flags. Thanks. - Alex