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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 52949C3A59E for ; Wed, 21 Aug 2019 08:05:22 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0FCF222D6D for ; Wed, 21 Aug 2019 08:05:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0FCF222D6D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8B7B66B02A5; Wed, 21 Aug 2019 04:05:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 868B36B02A6; Wed, 21 Aug 2019 04:05:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 77D6B6B02A7; Wed, 21 Aug 2019 04:05:21 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0162.hostedemail.com [216.40.44.162]) by kanga.kvack.org (Postfix) with ESMTP id 50A776B02A5 for ; Wed, 21 Aug 2019 04:05:21 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id E4A6C181AC9CC for ; Wed, 21 Aug 2019 08:05:20 +0000 (UTC) X-FDA: 75845700000.28.taste83_68c0eedc33a01 X-HE-Tag: taste83_68c0eedc33a01 X-Filterd-Recvd-Size: 2899 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Wed, 21 Aug 2019 08:05:19 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 8EA65AD95; Wed, 21 Aug 2019 08:05:17 +0000 (UTC) Date: Wed, 21 Aug 2019 10:05:16 +0200 From: Michal Hocko To: Yafang Shao Cc: Roman Gushchin , "akpm@linux-foundation.org" , "linux-mm@kvack.org" , Randy Dunlap , Johannes Weiner , Vladimir Davydov , Tetsuo Handa , Souptick Joarder , Yafang Shao Subject: Re: [PATCH v2] mm, memcg: skip killing processes under memcg protection at first scan Message-ID: <20190821080516.GZ3111@dhcp22.suse.cz> References: <1566177486-2649-1-git-send-email-laoar.shao@gmail.com> <20190820213905.GB12897@tower.DHCP.thefacebook.com> <20190821064452.GV3111@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) 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 Wed 21-08-19 15:26:56, Yafang Shao wrote: > On Wed, Aug 21, 2019 at 2:44 PM Michal Hocko wrote: > > > > On Wed 21-08-19 09:00:39, Yafang Shao wrote: > > [...] > > > More possible OOMs is also a strong side effect (and it prevent us > > > from using it). > > > > So why don't you use low limit if the guarantee side of min limit is too > > strong for you? > > Well, I don't know what the best-practice of memory.min is. It is really a workload reclaim protection. Say you have a memory consumer which performance characteristics would be noticeably disrupted by any memory reclaim which then would lead to SLA disruption. This is a strong requirement/QoS feature and as such comes with its demand on configuration. > In our plan, we want to use it to protect the top priority containers > (e.g. set the memory.min same with memory limit), which may latency > sensive. Using memory.min may sometimes decrease the refault. > If we set it too low, it may useless, becasue what memory.min is > protecting is not specified. And if there're some busrt anon memory > allocate in this memcg, the memory.min may can't protect any file > memory. I am still not seeing why you are considering guarantee (memory.min) rather than best practice (memory.low) here? -- Michal Hocko SUSE Labs