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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FEBAC433EF for ; Tue, 4 Jan 2022 20:30:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 08C856B0071; Tue, 4 Jan 2022 15:30:07 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 03BDA6B0072; Tue, 4 Jan 2022 15:30:07 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E1E7C6B0073; Tue, 4 Jan 2022 15:30:06 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0108.hostedemail.com [216.40.44.108]) by kanga.kvack.org (Postfix) with ESMTP id D25126B0071 for ; Tue, 4 Jan 2022 15:30:06 -0500 (EST) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 8D9488E2D8 for ; Tue, 4 Jan 2022 20:30:06 +0000 (UTC) X-FDA: 78993746412.01.CDDC10B Received: from mail-il1-f179.google.com (mail-il1-f179.google.com [209.85.166.179]) by imf29.hostedemail.com (Postfix) with ESMTP id 100A612000A for ; Tue, 4 Jan 2022 20:29:58 +0000 (UTC) Received: by mail-il1-f179.google.com with SMTP id q6so29196476ilt.6 for ; Tue, 04 Jan 2022 12:30:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=bul4qlld97QBjtDSOOsdxIpEMimKYTW5dlcNbaowlwI=; b=mtOJsGe1HP0q/Qhh/bycX0h7Jl/2jwzWfmiCyFlRg7R9A2TbdfKxdP8MT5k8D3hwYG dT7Ui1OUrpbhvH9QaHr78W0WdOnp64FBmr+S7Q0Vpeg5LpyfuffPNRR9HI3Xbxe8isPN F1Sjctn+bJI+/w+T9FmffZPNjQUR5pzoQaQXQWByf530JChpNIL06htkS0sLXiE/CxEA gLcuxfQ6BwNSvI3d995Wjh3kaRM06X91TN6q8ctqymYXrDluJ4ns16GLmg4BF0TWfb+K rTRwjSYscljigBMSX1uYI63ZSp0B+NmdoJSZ0rSu3In2kLIawYXWswXTAj4tL5YXTQGP BRSw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=bul4qlld97QBjtDSOOsdxIpEMimKYTW5dlcNbaowlwI=; b=moldTljmRDnVRKZcseWLQ9+b3w6N8YSC6OFOiAiPzz/hvKX2SHSIQYCDhUzJi6CVt7 myzHFpGmI5EpmvRTSSyMPBntNYHsYtQ0hlQZulufS2YHNWls+5smxyyLOWG+v2oF8j+F 4ij1FPXxWFHZM5hfnNeNs5qrvI4Tc1/c7lWf5na1c7kRZ40PfmnBC1gSiRbnKhE+9QuB ojPw1hgdcsdCriP+8axPl3IrM/zoA44leocHdcA01MP3frfIa8XUZ1c6SrXZsyqUA0Jp ib0LOwkIidGBD1KyLNi4HLtUjlMGM/eZGt7xP3ORiHvLgmo4Vqy11U3RsQZ2MbzRMA1y xXPQ== X-Gm-Message-State: AOAM533WRTHOGeeeFzbw7dRhzROp6vvlgmIiRDCC4lUSOpL1AmhVw9N3 iX7LAiHDsCtlRdP0IYINvVuEww== X-Google-Smtp-Source: ABdhPJwvrfas8nfe+PA6BOX0tHt36uxsoseV9gaRTUzX91V4WBmk/Mv40lM9zPNj86T6Z6k0gl7T1Q== X-Received: by 2002:a05:6e02:1567:: with SMTP id k7mr23098838ilu.46.1641328205445; Tue, 04 Jan 2022 12:30:05 -0800 (PST) Received: from google.com ([2620:15c:183:200:6c8c:5506:7ca2:9dfd]) by smtp.gmail.com with ESMTPSA id k13sm29592220iow.45.2022.01.04.12.30.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Jan 2022 12:30:05 -0800 (PST) Date: Tue, 4 Jan 2022 13:30:00 -0700 From: Yu Zhao To: Andrew Morton , Linus Torvalds Cc: Andi Kleen , Catalin Marinas , Dave Hansen , Hillf Danton , Jens Axboe , Jesse Barnes , Johannes Weiner , Jonathan Corbet , Matthew Wilcox , Mel Gorman , Michael Larabel , Michal Hocko , Rik van Riel , Vlastimil Babka , Will Deacon , Ying Huang , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, page-reclaim@google.com, x86@kernel.org Subject: Re: [PATCH v6 0/9] Multigenerational LRU Framework Message-ID: References: <20220104202227.2903605-1-yuzhao@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220104202227.2903605-1-yuzhao@google.com> X-Rspamd-Queue-Id: 100A612000A X-Stat-Signature: xf5rucrttfx7ar73oz3i1a7y71keifaa Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=mtOJsGe1; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf29.hostedemail.com: domain of yuzhao@google.com designates 209.85.166.179 as permitted sender) smtp.mailfrom=yuzhao@google.com X-Rspamd-Server: rspam02 X-HE-Tag: 1641328198-799436 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Jan 04, 2022 at 01:22:19PM -0700, Yu Zhao wrote: > TLDR > ==== > The current page reclaim is too expensive in terms of CPU usage and it > often makes poor choices about what to evict. This patchset offers an > alternative solution that is performant, versatile and > straightforward. > Summery > ======= > The facts are: > 1. The independent lab results and the real-world applications > indicate substantial improvements; there are no known regressions. > 2. Thrashing prevention, working set estimation and proactive reclaim > work out of the box; there are no equivalent solutions. > 3. There is a lot of new code; nobody has demonstrated smaller changes > with similar effects. > > Our options, accordingly, are: > 1. Given the amount of evidence, the reported improvements will likely > materialize for a wide range of workloads. > 2. Gauging the interest from the past discussions [14][15][16], the > new features will likely be put to use for both personal computers > and data centers. > 3. Based on Google's track record, the new code will likely be well > maintained in the long term. It'd be more difficult if not > impossible to achieve similar effects on top of the existing > design. Hi Andrew, Linus, Can you please take a look at this patchset and let me know if it's 5.17 material? My goal is to get it merged asap so that users can reap the benefits and I can push the sequels. Please examine the data provided -- I think the unprecedented coverage and the magnitude of the improvements warrant a green light. Thanks!