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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham 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 01980C04EB9 for ; Wed, 5 Dec 2018 22:12:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B604B2146D for ; Wed, 5 Dec 2018 22:12:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="YB/J577i" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B604B2146D Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728628AbeLEWMj (ORCPT ); Wed, 5 Dec 2018 17:12:39 -0500 Received: from mail-pg1-f172.google.com ([209.85.215.172]:46816 "EHLO mail-pg1-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727436AbeLEWMi (ORCPT ); Wed, 5 Dec 2018 17:12:38 -0500 Received: by mail-pg1-f172.google.com with SMTP id w7so9635703pgp.13 for ; Wed, 05 Dec 2018 14:12:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=bOkGwvP31kN5Ew8Q2svXxO1KvIXHlO3WMJDaHlzXfSA=; b=YB/J577iuGoIZlODm/GS0Rj4Q6e73Bm4BEih9Grjxh4Z/jS0AxcMOlzYXsKZb91eHb ZF7qSO6niAW98DIi90tZXzkv/snSyxnhfMgab5dCKMMIyPOBQxRPaf++Ui14fqcn93ia Re5+OzRjXq2h34NayVKCS0B7EbHf5XVtPDKgR6dq/7p5bMxAfcU6JkpduShDNinBs4lm AzlPZa5XmrczD9W+o09GGCukaqUYHpd9WB+pPkIk1J7Y+8YENH2SgatFfadNdJiX02fs YO+I9JuJc/8dn/+oZ7B/8eZVq+jw9cTR1MEXc4+z8qGBKP3ndrhfNRKkuYKPTqp+9E39 GLlQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version; bh=bOkGwvP31kN5Ew8Q2svXxO1KvIXHlO3WMJDaHlzXfSA=; b=t5r1HT3JxkBJMMyr3hm9cSL1WFm543e5mKFdpWEyeZjSQ3wqti89J0kB2A3maRIjGi tX6fyue71zxVLfpwqZ5NrCpRNHgh3APfZlCg9F7BG5SvqlsrF5PtSwHO8hQEmejdiwDz hZwjO0P5OZovYowqOPWsDRJH3IU54YrcSp9PgmJ3JgGd+E90IDQfIKnHd6nXlQFLM245 svuEElbftbdsSODzffeRhbq65MhuEHHb4Wq4HmWAiWytI+dkM9oOnLeH5szjyHb+PMNO LvOM/0xgpAYhuplP1ucjltWC3SPfXe2VKmMbWcPOiAjoY/TckEamgFuk72oIrjZuLArO MpXg== X-Gm-Message-State: AA+aEWb62++r9C14PEnEwgAVg2UWVLv7+9XAs4Ej6YnNXbEaPvShTfjo tcCoVYPp2oZu0vBB59vb1//v5Q== X-Google-Smtp-Source: AFSGD/XbL3/CYP5q39VKca14xIUA8syMwb/JZAsRwacBdzOm2HkGc/vSXyeP/onEluPhJQjvuhBfKg== X-Received: by 2002:a62:345:: with SMTP id 66mr25932095pfd.189.1544047957983; Wed, 05 Dec 2018 14:12:37 -0800 (PST) Received: from [2620:15c:17:3:3a5:23a7:5e32:4598] ([2620:15c:17:3:3a5:23a7:5e32:4598]) by smtp.gmail.com with ESMTPSA id s2sm35207261pfa.167.2018.12.05.14.12.36 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 05 Dec 2018 14:12:37 -0800 (PST) Date: Wed, 5 Dec 2018 14:12:35 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Linus Torvalds cc: Andrea Arcangeli , mgorman@techsingularity.net, Vlastimil Babka , mhocko@kernel.org, ying.huang@intel.com, s.priebe@profihost.ag, Linux List Kernel Mailing , alex.williamson@redhat.com, lkp@01.org, kirill@shutemov.name, Andrew Morton , zi.yan@cs.rutgers.edu Subject: Re: [LKP] [mm] ac5b2c1891: vm-scalability.throughput -61.3% regression In-Reply-To: Message-ID: References: <20181203183050.GL31738@dhcp22.suse.cz> <20181203185954.GM31738@dhcp22.suse.cz> <20181203201214.GB3540@redhat.com> <64a4aec6-3275-a716-8345-f021f6186d9b@suse.cz> <20181204104558.GV23260@techsingularity.net> <20181205204034.GB11899@redhat.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 5 Dec 2018, Linus Torvalds wrote: > > So ultimately we decided that the saner behavior that gives the least > > risk of regression for the short term, until we can do something > > better, was the one that is already applied upstream. > > You're ignoring the fact that people *did* report things regressed. > > That's the part I find unacceptable. You're saying "we picked > something that minimized regressions". > > No it didn't. The regression is present and real, and is on a real > load, not a benchmark. > > So that argument is clearly bogus. > > I'm going to revert the commit since people apparently seem to be > ignoring this fundamental issue. > > Real workloads regressed. The regressions got reported. Ignoring that > isn't acceptable. > Please allow me to prepare my v2 because it's not a clean revert due to the follow-up 89c83fb539f9 ("mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask") and will incorporate the feedback from Michal to not change anything outside of the thp fault path.