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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 9977AC433E0 for ; Tue, 2 Feb 2021 22:35:15 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 511A264F2C for ; Tue, 2 Feb 2021 22:35:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 511A264F2C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CF2436B006C; Tue, 2 Feb 2021 17:35:14 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C2EC46B006E; Tue, 2 Feb 2021 17:35:14 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B1D346B0070; Tue, 2 Feb 2021 17:35:14 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0068.hostedemail.com [216.40.44.68]) by kanga.kvack.org (Postfix) with ESMTP id 934E46B006C for ; Tue, 2 Feb 2021 17:35:14 -0500 (EST) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 4AFFB1EF1 for ; Tue, 2 Feb 2021 22:35:14 +0000 (UTC) X-FDA: 77774784948.02.ghost08_5802518275ce Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id 2513810097AA1 for ; Tue, 2 Feb 2021 22:35:14 +0000 (UTC) X-HE-Tag: ghost08_5802518275ce X-Filterd-Recvd-Size: 4049 Received: from mail-ej1-f51.google.com (mail-ej1-f51.google.com [209.85.218.51]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Tue, 2 Feb 2021 22:35:13 +0000 (UTC) Received: by mail-ej1-f51.google.com with SMTP id jj19so4802214ejc.4 for ; Tue, 02 Feb 2021 14:35:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=BDIEFbGB+Z7Bn8D9m+hjMBU/S6ekRDtx1605yvM6W24=; b=rvjMeg4Wt3xH9v8WYsMzwnJa492nEMHSslmICRIJml17tx15n70Ow3wC+e779rf4TW b39WCNad2oIcvP3YcOWHI7CfrRcJx3au2dwb4E6rTW3dvJ6z/3tF2IJenRYZsoAohn5U bc6HB2TmH9fYqzlZjpic/nBqDO+E8C0rNH3k6/OHYmP7q7QdqNHU5oK1ZjGCrGa+K7dx Mn7eZcJ5cBQZ853EzmoHLUgv1phBCrR7oVwry1xq+seJGSsbreKg4K8/ThDXGOQ8mvf4 1x7s/GYDaCUKco71C2m90RUvLIIbom9ps7zbQ/5bpLPh3ns7EEiIzkjVRqLN2rBvMHXD ft+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=BDIEFbGB+Z7Bn8D9m+hjMBU/S6ekRDtx1605yvM6W24=; b=omyfGRAJ5z2A3Oec3ffRGQbtpTUPPWle39umNOKzu2hiD1oGJzG22bsBMXbKIir3HK S83TxS5BRPI4Z+D9CP28vkH2i1vIwo52xNN0vtHcYgVjwzI/wBk68yB1u1uPALrapzJt dcAOOZ4rwxhfTyp421XC3Gct7lPlGekFD2UrdZndmrIkuI5pooKCU4Yl+hh8I0Fh/SzW B0HkweG4mJj53pCoSAyHE+59thw6kTIhU384qVJeouWtBSJDrWLf4tMypR6Lq1BMqp+p 1OPVma3obBybuoVBRseIqEwnoFMrDoiMGFxPik8ab4osrjErrrSZsZK5MGkgS8i+LD/6 ZIBg== X-Gm-Message-State: AOAM531Em1PD7FCY0KV6THroAPBiyc+qBzmqswTnSLC9v8Ef3eKQ8njR xoqD72PUp/c2QqF7s9g2NgQzT+5WTJLq9CtOIM4lw5K6NTY= X-Google-Smtp-Source: ABdhPJzWJan42RtYOqBFlZYEeOtLMaMs/xKo/NE8t5jKz+FGiUy4upEXvijk9zHEOL+PNnt8fXwkjetgE3hrnemP2w8= X-Received: by 2002:a17:906:3945:: with SMTP id g5mr202863eje.514.1612305312460; Tue, 02 Feb 2021 14:35:12 -0800 (PST) MIME-Version: 1.0 References: <20210126003411.2AC51464@viggo.jf.intel.com> <20210126003432.6E88B570@viggo.jf.intel.com> <21785ed9-9591-e070-0941-6113999fa69e@intel.com> In-Reply-To: <21785ed9-9591-e070-0941-6113999fa69e@intel.com> From: Yang Shi Date: Tue, 2 Feb 2021 14:35:00 -0800 Message-ID: Subject: Re: [RFC][PATCH 11/13] mm/vmscan: Consider anonymous pages without swap To: Dave Hansen Cc: Dave Hansen , Linux Kernel Mailing List , Linux MM , kbusch@kernel.org, "Verma, Vishal L" , Yang Shi , David Rientjes , Huang Ying , Dan Williams , David Hildenbrand , Oscar Salvador Content-Type: text/plain; charset="UTF-8" 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, Feb 2, 2021 at 1:35 PM Dave Hansen wrote: > > On 2/2/21 10:56 AM, Yang Shi wrote: > >> > >> /* If we have no swap space, do not bother scanning anon pages. */ > >> - if (!sc->may_swap || mem_cgroup_get_nr_swap_pages(memcg) <= 0) { > >> + if (!sc->may_swap || !can_reclaim_anon_pages(memcg, pgdat->node_id)) { > > Just one minor thing about may_swap. It may be cleared by > > nr_boost_reclaim. But demotion should be fine for boost_reclaim. > > In other words, this if() is here is to avoid generating suboptimal I/O > during boost_reclaim. But, since demotion doesn't generate any I/O, it > *should* be fine for boost_reclaim. > > I agree with that in theory. Although, I'm tempted to put it in the > TODO list as something to look at in the future. Do you think it's > something that's immediately necessary? No, I don't think so. We could tweak this later on.