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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 38A05C43387 for ; Fri, 21 Dec 2018 22:15:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0296A21920 for ; Fri, 21 Dec 2018 22:15:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="KHfOqRy4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403775AbeLUWPR (ORCPT ); Fri, 21 Dec 2018 17:15:17 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:42162 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730887AbeLUWPQ (ORCPT ); Fri, 21 Dec 2018 17:15:16 -0500 Received: by mail-pl1-f194.google.com with SMTP id y1so3061854plp.9 for ; Fri, 21 Dec 2018 14:15:15 -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=1oXyv+hyR8LAS/wcEoKMlkajidxeADrKp4+muhyFn0c=; b=KHfOqRy4hLY3Oy5yLkM42F1EPhIhiAXcW1H5J5OdX1KxMx+E/Gp15PXT+y6p/rXQXp uuP4VXAtjRs/uFL+37Sgst66A6djQM21LfrMtL4qABYaf/XVx0xOPzCc7TVB6WN7nCPg FsleqKf4mrPDCtbSUbW+2TIQnq2+udupd9McFfKBrQgCvYfTHTLQoeMZQCCRQK0wstu/ asVkwp7zd+268ywl1J561G268eluABV2uRrs9fEKVYw8a/px5FbfMfIZfhMQSkiSNqsN lCAfueQiItSFmDQBhmFgPLWFrqOraq7+x7uj3EcEMjmLw45dXB8QII3PYYyMA6WG0Jn3 /cLw== 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=1oXyv+hyR8LAS/wcEoKMlkajidxeADrKp4+muhyFn0c=; b=JnuBnOt1vJazBz4k6zhCd9abtk63s6QhrNuuCtPKwh3HYzHVB47i1bPmwyxl62A530 +10X64x6JFVIB4YZ34ybA7uMg2/a2FA5wJVC6fwApEkE9A64qM+YvE+5AohxZh4pib2n FeZXS+Ky05tZwfhljNku/e/iRS/zFUEhZ6F6oSt0fZt3dfbRokbTkzERL6tI/luGjGlO Z5BBSIwiQTFM9Umd/LCi5IDrLQYh+f32+ByMzTu3spQR8m6C6rK5MH+3fBoHuQ+vu98i A13ANB8zA/62/MeRER5vampybKNd5QrwYFWJBdjRy4nGsBxAbujtFtzyYxwHPiUZ3B8l e8KA== X-Gm-Message-State: AJcUukd6fONXtmLEnUMUhg1nDSaV4g8C70KR3SpVR0sDtDgCfbfBR5jT c0WzvYAshMn01PVPbt/iwAsXZQ== X-Google-Smtp-Source: ALg8bN61JHwQD5PoDYot8kCjn+AxI5JKGu4kRewRO5jfN3lnoBSO3+72x7DIKlO4nOe1wwAI2d/bvw== X-Received: by 2002:a17:902:4225:: with SMTP id g34mr4379112pld.152.1545430514776; Fri, 21 Dec 2018 14:15:14 -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 p2sm33052806pfp.125.2018.12.21.14.15.05 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 21 Dec 2018 14:15:05 -0800 (PST) Date: Fri, 21 Dec 2018 14:15:05 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Mel Gorman cc: Vlastimil Babka , Andrea Arcangeli , Linus Torvalds , Michal Hocko , 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: <20181214231147.GF29005@techsingularity.net> Message-ID: References: <20181205233632.GE11899@redhat.com> <20181210044916.GC24097@redhat.com> <0bbf4202-6187-28fb-37b7-da6885b89cce@suse.cz> <20181214231147.GF29005@techsingularity.net> 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 Fri, 14 Dec 2018, Mel Gorman wrote: > > In other words, I think there is a lot of potential stranding that occurs > > for both scanners that could otherwise result in completely free > > pageblocks. If there a single movable page present near the end of the > > zone in an otherwise fully free pageblock, surely we can do better than > > the current implementation that would never consider this very easy to > > compact memory. > > > > While it's somewhat premature, I posted a series before I had a full set > of results because it uses free lists to reduce searches and reduces > inference between multiple scanners. Preliminary results indicated it > boosted allocation success rates by 20%ish, reduced migration scanning > by 99% and free scanning by 27%. > Always good to have code to look at, I'll take a closer look. I've unfortunately been distracted with other kernel issues lately :/