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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 74550C432C0 for ; Mon, 18 Nov 2019 10:29:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3CE5C20730 for ; Mon, 18 Nov 2019 10:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574072994; bh=W9BIF1OvkiWWCFprCcq9hetIt2pM1V1C6tTsW2kMv1A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=WPhtcFeb9kegQtKrzJETpsOXkwSe8c3xHvP5F0kIO82z2E6pc1oJYxG65tGrE/t26 Rv0sRquKZVIXXAEqDS7dutdpvfhdZ8ZS5VWhNu+J+LH2Qi/XyRxk6eNu3Mr4GTw0AT Kh/CYYcfrnQKefbvMp1F7XbAYg9Qztl5RvncvUWM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726596AbfKRK3x (ORCPT ); Mon, 18 Nov 2019 05:29:53 -0500 Received: from mx2.suse.de ([195.135.220.15]:38984 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726518AbfKRK3w (ORCPT ); Mon, 18 Nov 2019 05:29:52 -0500 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 56444AE89; Mon, 18 Nov 2019 10:29:51 +0000 (UTC) Date: Mon, 18 Nov 2019 11:29:50 +0100 From: Michal Hocko To: Hillf Danton Cc: linux-mm , Rong Chen , linux-kernel Subject: Re: [RFC v3] memcg: add memcg lru Message-ID: <20191118102950.GB14255@dhcp22.suse.cz> References: <20191117113526.5640-1-hdanton@sina.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191117113526.5640-1-hdanton@sina.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun 17-11-19 19:35:26, Hillf Danton wrote: > > Currently soft limit reclaim (slr) is frozen, see > Documentation/admin-guide/cgroup-v2.rst for reasons. > > This work adds memcg hook into kswapd's logic to bypass slr, paving > a brick for its cleanup later. > > After b23afb93d317 ("memcg: punt high overage reclaim to > return-to-userland path"), high limit breachers (hlb) are reclaimed > one after another spiraling up through the memcg hierarchy before > returning to userspace. > > The current memcg high work helps to add the lru because we get to > collect hlb at zero price and in particular without adding changes > to the high work's behavior. > > Then a fifo list, which is essencially a simple copy of the page lru, > is needed to facilitate queuing up hlb and ripping pages off them in > round robin once kswapd starts doing its job. > > Finally new hook is added with slr's two problems addressed i.e. > hierarchy-unaware reclaim and overreclaim. > > Thanks to Rong Chen for testing. You have ignored the previous review feedback again [1]. I have nacked the patch on grounds that it is completely missing any real use case scenario or any numbers suggesting there is an actual improvement. Please do not post new versions until you make those things clear. [1] http://lkml.kernel.org/r/20191029083730.GC31513@dhcp22.suse.cz -- Michal Hocko SUSE Labs