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 232A2C433F5 for ; Sat, 16 Apr 2022 00:03:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 571166B0072; Fri, 15 Apr 2022 20:03:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 520B46B0073; Fri, 15 Apr 2022 20:03:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3C1046B0074; Fri, 15 Apr 2022 20:03:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 2CF816B0072 for ; Fri, 15 Apr 2022 20:03:55 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id EB6F161F23 for ; Sat, 16 Apr 2022 00:03:54 +0000 (UTC) X-FDA: 79360793988.13.7CADC98 Received: from mail-vs1-f51.google.com (mail-vs1-f51.google.com [209.85.217.51]) by imf22.hostedemail.com (Postfix) with ESMTP id 631DDC0003 for ; Sat, 16 Apr 2022 00:03:54 +0000 (UTC) Received: by mail-vs1-f51.google.com with SMTP id f32so8186316vsv.1 for ; Fri, 15 Apr 2022 17:03:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ztOn9qTNjZOdib9wu9VtT2ux2AzPcxh/m+7PKVCw6iQ=; b=R5JSg0OZdet4qAUAD70eGrmGlbnfq6SE/UKMx9mVP3XjOuHnA4bSF78m1q8xItuGE9 vjqnxSxQ4spxqIw4T67UAoX/WAcpVdYRh0Do8X6bcppYXWpUgrN8T6JkIEu/GY1wQYyh A68dT7GLg+KlcZh58eo3TpGvYK6OsZzyfMZQDrLE0MQ6uR9X86jvNVceMpuK6ksQ1AGF vNgu+/XSqK9byqpg3ekX51zXiD0AKThWb3YM076hxyjIsBkx1tLG5G2nPZKahaiU1EQ/ FUnVlc5HTy63gEsQMroqaIki707KQUKD83kXincChwkr/HdyaaFWnemn3Dfdf9e2bpd8 6Bgg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ztOn9qTNjZOdib9wu9VtT2ux2AzPcxh/m+7PKVCw6iQ=; b=nx8lWPB3WEhkUwmSWhAXsUXb8vm3aHf34tdjoboZ4Vcljr8Dt2JNX1Y8FB7qaJt4+B yPC692Q47I/p6UgOEYtH1BJvON71b1vBW5BqiIhAmPevp0BZ+yPMlSkdIEIkRKoZEApS PF43pDxOc2kTT8pKEDIhYDVniEB8i4RSgUoE6BM6KNxB4ELatgCUBwjGZjyVtnMNGmjL DWzd+WKuQOpi6VuMbR1LC47nfhls+MQnNs7XSXYYi/j4MyUxNGKnYH36hej0+420tVpQ MHgzT307acNcHF6rwyatlAn0ly46P815DxQY1DdhYmm0ZGuGt8nql3DQZelHoFrTdB7Y STRg== X-Gm-Message-State: AOAM531d7JQX7YvotuQKfjZK0kwWxKLwYq+FZOmUbgq18RObIZ10+NFW bA43IY0IvSDZPVl/NdUcDx+rXg1Kl7LOUcm4HmndrA== X-Google-Smtp-Source: ABdhPJw2ERJ54VhqBYtjNfKf1yIUSVFp1Wz9yRWf2I17eE6bxYiU0nBVH1Y+brrNjKX5bhrMgcp/2etChjEHOe5V/60= X-Received: by 2002:a05:6102:3753:b0:325:c20e:4b1c with SMTP id u19-20020a056102375300b00325c20e4b1cmr371331vst.84.1650067433140; Fri, 15 Apr 2022 17:03:53 -0700 (PDT) MIME-Version: 1.0 References: <20220407031525.2368067-1-yuzhao@google.com> <20220407031525.2368067-13-yuzhao@google.com> <20220411191634.674554d3de2ba37b3db40ca2@linux-foundation.org> In-Reply-To: <20220411191634.674554d3de2ba37b3db40ca2@linux-foundation.org> From: Yu Zhao Date: Fri, 15 Apr 2022 18:03:16 -0600 Message-ID: Subject: Re: [PATCH v10 12/14] mm: multi-gen LRU: debugfs interface To: Andrew Morton Cc: Stephen Rothwell , Linux-MM , Andi Kleen , Aneesh Kumar , Barry Song <21cnbao@gmail.com>, Catalin Marinas , Dave Hansen , Hillf Danton , Jens Axboe , Jesse Barnes , Johannes Weiner , Jonathan Corbet , Linus Torvalds , Matthew Wilcox , Mel Gorman , Michael Larabel , Michal Hocko , Mike Rapoport , Rik van Riel , Vlastimil Babka , Will Deacon , Ying Huang , Linux ARM , "open list:DOCUMENTATION" , linux-kernel , Kernel Page Reclaim v2 , "the arch/x86 maintainers" , Brian Geffon , Jan Alexander Steffens , Oleksandr Natalenko , Steven Barrett , Suleiman Souhlal , Daniel Byrne , Donald Carr , =?UTF-8?Q?Holger_Hoffst=C3=A4tte?= , Konstantin Kharlamov , Shuang Zhai , Sofia Trinh , Vaibhav Jain Content-Type: text/plain; charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 631DDC0003 X-Stat-Signature: 8186gh9jxafbsxscfesf5aaiwjr7y8dr Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=R5JSg0OZ; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf22.hostedemail.com: domain of yuzhao@google.com designates 209.85.217.51 as permitted sender) smtp.mailfrom=yuzhao@google.com X-HE-Tag: 1650067434-632465 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 Mon, Apr 11, 2022 at 8:16 PM Andrew Morton wrote: > > On Wed, 6 Apr 2022 21:15:24 -0600 Yu Zhao wrote: > > > Add /sys/kernel/debug/lru_gen for working set estimation and proactive > > reclaim. These features are required to optimize job scheduling (bin > > packing) in data centers [1][2]. > > debugfs is for ephemeral temp stuf which can and will change or > disappear at any time. Anything which is "required" by userspace > should not be in debufgs. Right. "required" is probably a poor choice of words. "These techniques are commonly used to optimize job scheduling" would sound better. > Presumably sysfs is the place. Fully documented and with usage > examples in the changelog so we can carefully review the proposed > extensions to Linux's ABI. Extensions which must be maintained > unchanged for all time. Eventually, yes. There still is a long way to go. Rest assured, this is something Google will keep investing resources on.