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=-0.6 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 24D9DC04EBF for ; Mon, 23 Sep 2019 13:05:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C58A5207FD for ; Mon, 23 Sep 2019 13:05:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C58A5207FD 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 666A26B0006; Mon, 23 Sep 2019 09:05:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 616E66B0008; Mon, 23 Sep 2019 09:05:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 52BEB6B000A; Mon, 23 Sep 2019 09:05:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0173.hostedemail.com [216.40.44.173]) by kanga.kvack.org (Postfix) with ESMTP id 2CA4F6B0006 for ; Mon, 23 Sep 2019 09:05:15 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id BB11B16B11 for ; Mon, 23 Sep 2019 13:05:14 +0000 (UTC) X-FDA: 75966206148.10.sheet81_84eb0f866940e X-HE-Tag: sheet81_84eb0f866940e X-Filterd-Recvd-Size: 2377 Received: from r3-24.sinamail.sina.com.cn (r3-24.sinamail.sina.com.cn [202.108.3.24]) by imf40.hostedemail.com (Postfix) with SMTP for ; Mon, 23 Sep 2019 13:05:13 +0000 (UTC) Received: from unknown (HELO localhost.localdomain)([111.194.183.187]) by sina.com with ESMTP id 5D88C3040002EC0B; Mon, 23 Sep 2019 21:05:10 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com X-SMAIL-MID: 67170054921480 From: Hillf Danton To: Michal Hocko Cc: Hillf Danton , Johannes Weiner , Andrew Morton , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , Shakeel Butt , Roman Gushchin , Matthew Wilcox Subject: Re: [RFC] mm: memcg: add priority for soft limit reclaiming Date: Mon, 23 Sep 2019 21:04:59 +0800 Message-Id: <20190923130459.11072-1-hdanton@sina.com> 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 Thu, 19 Sep 2019 21:32:31 +0800 Michal Hocko wrote: >=20 > On Thu 19-09-19 21:13:32, Hillf Danton wrote: > > > > Currently memory controler is playing increasingly important role in > > how memory is used and how pages are reclaimed on memory pressure. > > > > In daily works memcg is often created for critical tasks and their pr= e > > configured memory usage is supposed to be met even on memory pressure= . > > Administrator wants to make it configurable that the pages consumed b= y > > memcg-B can be reclaimed by page allocations invoked not by memcg-A b= ut > > by memcg-C. >=20 > I am not really sure I understand the usecase well but this sounds like > what memory reclaim protection in v2 is aiming at. >=20 A tipoint to the v2 stuff please. > > That configurability is addressed by adding priority for soft limit > > reclaiming to make sure that no pages will be reclaimed from memcg of > > higer priortiy in favor of memcg of lower priority. >=20 > cgroup v1 interfaces are generally frozen and mostly aimed at backward > compatibility. I am especially concerned about adding a new way to > control soft limit which is known to be misdesigned and unfixable to > behave reasonably. > An URL to the drafts/works about the new way in your git tree. Thanks Hillf