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=-2.5 required=3.0 tests=MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT 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 18451C04EB9 for ; Mon, 3 Dec 2018 18:59:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF74C20848 for ; Mon, 3 Dec 2018 18:59:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF74C20848 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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 S1726979AbeLCTAA (ORCPT ); Mon, 3 Dec 2018 14:00:00 -0500 Received: from mx2.suse.de ([195.135.220.15]:47542 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725987AbeLCTAA (ORCPT ); Mon, 3 Dec 2018 14:00:00 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 1C293AF31; Mon, 3 Dec 2018 18:59:55 +0000 (UTC) Date: Mon, 3 Dec 2018 19:59:54 +0100 From: Michal Hocko To: Linus Torvalds Cc: ying.huang@intel.com, Andrea Arcangeli , s.priebe@profihost.ag, mgorman@techsingularity.net, Linux List Kernel Mailing , alex.williamson@redhat.com, lkp@01.org, David Rientjes , kirill@shutemov.name, Andrew Morton , zi.yan@cs.rutgers.edu, Vlastimil Babka Subject: Re: [LKP] [mm] ac5b2c1891: vm-scalability.throughput -61.3% regression Message-ID: <20181203185954.GM31738@dhcp22.suse.cz> References: <20181127062503.GH6163@shao2-debian> <20181127205737.GI16136@redhat.com> <87tvk1yjkp.fsf@yhuang-dev.intel.com> <20181203181456.GK31738@dhcp22.suse.cz> <20181203183050.GL31738@dhcp22.suse.cz> 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) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 03-12-18 10:45:35, Linus Torvalds wrote: > On Mon, Dec 3, 2018 at 10:30 AM Michal Hocko wrote: > > > > I do not get it. 5265047ac301 which this patch effectively reverts has > > regressed kvm workloads. People started to notice only later because > > they were not running on kernels with that commit until later. We have > > 4.4 based kernels reports. What do you propose to do for those people? > > We have at least two patches that others claim to fix things. > > You dismissed them and said "can't be done". You are misinterpreting my words. I haven't dismissed anything. I do recognize both usecases under discussion. I have merely said that a better THP locality needs more work and during the review discussion I have even volunteered to work on that. There are other reclaim related fixes under work right now. All I am saying is that MADV_TRANSHUGE having numa locality implications cannot satisfy all the usecases and it is particurarly KVM that suffers from it. -- Michal Hocko SUSE Labs From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============3564588892558581620==" MIME-Version: 1.0 From: Michal Hocko To: lkp@lists.01.org Subject: Re: [mm] ac5b2c1891: vm-scalability.throughput -61.3% regression Date: Mon, 03 Dec 2018 19:59:54 +0100 Message-ID: <20181203185954.GM31738@dhcp22.suse.cz> In-Reply-To: List-Id: --===============3564588892558581620== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable On Mon 03-12-18 10:45:35, Linus Torvalds wrote: > On Mon, Dec 3, 2018 at 10:30 AM Michal Hocko wrote: > > > > I do not get it. 5265047ac301 which this patch effectively reverts has > > regressed kvm workloads. People started to notice only later because > > they were not running on kernels with that commit until later. We have > > 4.4 based kernels reports. What do you propose to do for those people? > = > We have at least two patches that others claim to fix things. > = > You dismissed them and said "can't be done". You are misinterpreting my words. I haven't dismissed anything. I do recognize both usecases under discussion. I have merely said that a better THP locality needs more work and during the review discussion I have even volunteered to work on that. There are other reclaim related fixes under work right now. All I am saying is that MADV_TRANSHUGE having numa locality implications cannot satisfy all the usecases and it is particurarly KVM that suffers from it. -- = Michal Hocko SUSE Labs --===============3564588892558581620==--