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=-2.5 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham 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 9B59AC282D7 for ; Wed, 30 Jan 2019 19:30:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70C9B20882 for ; Wed, 30 Jan 2019 19:30:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=cmpxchg-org.20150623.gappssmtp.com header.i=@cmpxchg-org.20150623.gappssmtp.com header.b="MBC71ieo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387629AbfA3Tae (ORCPT ); Wed, 30 Jan 2019 14:30:34 -0500 Received: from mail-yb1-f196.google.com ([209.85.219.196]:33013 "EHLO mail-yb1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387575AbfA3Tae (ORCPT ); Wed, 30 Jan 2019 14:30:34 -0500 Received: by mail-yb1-f196.google.com with SMTP id m132so316244ybf.0 for ; Wed, 30 Jan 2019 11:30:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=u4lGJa1eqm311IjOZIxyEEk5pH4RS2fwSIKRlT/c2bc=; b=MBC71ieoROyzpJYMm/RoM48yebOSHThzuo7d3oPiagXJfjLAD5AOCg12b0GXqJMHgo byQdg6fKygYXahH3gh70/beX8rcnd9A2w876UhzSUZRp1EC54kTTM02cUEIHzQF34GZP 9/ViuRdoaByPgSw4yx6n4p8Dlns+T5Pw4L87bee6Hw8nuxjJXB+l8mHHb+lYM9bSEsYh p5FehOxBq3izQVdqa3zLxdA2sCUSafZvMUY7D91qtNGspuKGT1tm/XhwTSyKShEMwbNq n0dQ3h57xSEY0s45uLv7teLyVuciOaDK0y8LFHR9WeANLuoFKihiVwRYKw4TT3+TpzQm g2Mg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=u4lGJa1eqm311IjOZIxyEEk5pH4RS2fwSIKRlT/c2bc=; b=R7H73/HSX7C3lfnNK56M2aT5jd8wn4e6xWCwY/boNZaUb0I5It/Rg0EiyKG4ivNb57 mcigafHUXoohdV0FQ1bApf5TpCEhMiHzRAi/dFU7G0YgjBZeJ0JR3rUIAFojZkcKiup+ aAI8Btp3rQiXXCffslmv1iiUGqisVdxg/ydchjPjE20z3Iv4JQZja0ksaBO9FO5dj57r iMJ4VG5dKcFE1bhWXHCJNommbDB0kVvnynIgZXuxT1wbUn/gs8wQzs/QfNzSJfO8pyMQ 0IOJ/vKSRAx3JRCgpWoLtBlYFpKTOl6GW3grhfcX3L3/5GEhT7EuNDuJV5tYTbBNT1fw uX3Q== X-Gm-Message-State: AJcUukfHNyY3L+CeryC0voVseGUhfnvT1r9Ik0NEphCHQ5SlHdS18a03 YgCBUrbPPlUkD3qeoVAOO8C4tg== X-Google-Smtp-Source: ALg8bN6aWM4PfrnEWZ0n7/syAfcjFDV7n2/VR+Rg6LPSuim4pyDJ52BuMPbRR8vl2JyQ6Vsoq/7SFg== X-Received: by 2002:a25:9001:: with SMTP id s1mr29449505ybl.493.1548876628452; Wed, 30 Jan 2019 11:30:28 -0800 (PST) Received: from localhost ([2620:10d:c091:200::5:6c95]) by smtp.gmail.com with ESMTPSA id c127sm789304ywb.67.2019.01.30.11.30.27 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 30 Jan 2019 11:30:27 -0800 (PST) Date: Wed, 30 Jan 2019 14:30:26 -0500 From: Johannes Weiner To: Shakeel Butt Cc: Tejun Heo , Michal Hocko , Chris Down , Andrew Morton , Roman Gushchin , Dennis Zhou , LKML , Cgroups , Linux MM , kernel-team@fb.com Subject: Re: [PATCH 2/2] mm: Consider subtrees in memory.events Message-ID: <20190130193026.GA21410@cmpxchg.org> References: <20190128151859.GO18811@dhcp22.suse.cz> <20190128154150.GQ50184@devbig004.ftw2.facebook.com> <20190128170526.GQ18811@dhcp22.suse.cz> <20190128174905.GU50184@devbig004.ftw2.facebook.com> <20190129144306.GO18811@dhcp22.suse.cz> <20190129145240.GX50184@devbig004.ftw2.facebook.com> <20190130165058.GA18811@dhcp22.suse.cz> <20190130170658.GY50184@devbig004.ftw2.facebook.com> <20190130192712.GA21279@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190130192712.GA21279@cmpxchg.org> User-Agent: Mutt/1.11.2 (2019-01-07) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 30, 2019 at 02:27:12PM -0500, Johannes Weiner wrote: > On Wed, Jan 30, 2019 at 11:11:44AM -0800, Shakeel Butt wrote: > > Hi Tejun, > > > > On Wed, Jan 30, 2019 at 9:07 AM Tejun Heo wrote: > > > > > > Hello, Michal. > > > > > > On Wed, Jan 30, 2019 at 05:50:58PM +0100, Michal Hocko wrote: > > > > > Yeah, cgroup.events and .stat files as some of the local stats would > > > > > be useful too, so if we don't flip memory.events we'll end up with sth > > > > > like cgroup.events.local, memory.events.tree and memory.stats.local, > > > > > which is gonna be hilarious. > > > > > > > > Why cannot we simply have memory.events_tree and be done with it? Sure > > > > the file names are not goin to be consistent which is a minus but that > > > > ship has already sailed some time ago. > > > > > > Because the overall cost of shitty interface will be way higher in the > > > longer term. cgroup2 interface is far from perfect but is way better > > > than cgroup1 especially for the memory controller. Why do you think > > > that is? > > > > > > > I thought you are fine with the separate interface for the hierarchical events. > > Every other file in cgroup2 is hierarchical, but for recursive > memory.events you'd need to read memory.events_tree? > > Do we hate our users that much? :( FTR, I would be okay with adding .local versions to existing files where such a behavior could be useful. But that seems to be a separate discussion from fixing memory.events here.