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=-0.7 required=3.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 89AD2C432C1 for ; Wed, 25 Sep 2019 02:35:46 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 11DD22146E for ; Wed, 25 Sep 2019 02:35:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 11DD22146E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 685D16B0007; Tue, 24 Sep 2019 22:35:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 636826B0008; Tue, 24 Sep 2019 22:35:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5244D6B000A; Tue, 24 Sep 2019 22:35:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0096.hostedemail.com [216.40.44.96]) by kanga.kvack.org (Postfix) with ESMTP id 2AEE56B0007 for ; Tue, 24 Sep 2019 22:35:45 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id B86CB180AD802 for ; Wed, 25 Sep 2019 02:35:44 +0000 (UTC) X-FDA: 75971877408.22.music16_8951d8f288e0c X-HE-Tag: music16_8951d8f288e0c X-Filterd-Recvd-Size: 2002 Received: from r3-25.sinamail.sina.com.cn (r3-25.sinamail.sina.com.cn [202.108.3.25]) by imf46.hostedemail.com (Postfix) with SMTP for ; Wed, 25 Sep 2019 02:35:43 +0000 (UTC) Received: from unknown (HELO localhost.localdomain)([111.194.183.187]) by sina.com with ESMTP id 5D8AD27B00033A61; Wed, 25 Sep 2019 10:35:40 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com X-SMAIL-MID: 93741054919305 From: Hillf Danton To: Roman Gushchin , Michal Hocko Cc: Hillf Danton , Johannes Weiner , Andrew Morton , linux , linux-mm , Shakeel Butt , Matthew Wilcox Subject: Re: [RFC] mm: memcg: add priority for soft limit reclaiming Date: Wed, 25 Sep 2019 10:35:30 +0800 Message-Id: <20190925023530.6364-1-hdanton@sina.com> In-Reply-To: <20190924133016.GT23050@dhcp22.suse.cz> References: <20190924073642.3224-1-hdanton@sina.com> <20190924133016.GT23050@dhcp22.suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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, 24 Sep 2019 17:23:35 +0000 from Roman Gushchin >=20 > On Tue, Sep 24, 2019 at 03:30:16PM +0200, Michal Hocko wrote: > > > > But really, make sure you look into the existing feature set that mem= cg > > v2 provides already and come back if you find it unsuitable and we ca= n > > move from there. Soft limit reclaim is dead and we should let it RIP. >=20 > Can't agree more here. >=20 > Cgroup v2 memory protection mechanisms (memory.low/min) should perfectl= y > solve the described problem. If not, let's fix them rather than extend = soft > reclaim which is already dead. >=20 Hehe, IIUC memory.low/min is essentially drawing a line that reclaimers would try their best not to cross. Page preemption OTOH is near ten miles away from that line though it is now on the shoulder of soft reclaiming.