From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753480AbdK0VrU (ORCPT ); Mon, 27 Nov 2017 16:47:20 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40804 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752380AbdK0VrS (ORCPT ); Mon, 27 Nov 2017 16:47:18 -0500 Subject: Re: [PATCH v3] cpuset: Enable cpuset controller in default hierarchy To: Tejun Heo Cc: Li Zefan , Johannes Weiner , Jonathan Corbet , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, Mike Galbraith , Christian Brauner , =?UTF-8?Q?St=c3=a9phane_Graber?= , Serge Hallyn References: <1507324230-22996-1-git-send-email-longman@redhat.com> <20171127210411.GS983427@devbig577.frc2.facebook.com> <8a5ba419-2b02-5b6a-462f-34106cc575ab@redhat.com> <20171127214232.GT983427@devbig577.frc2.facebook.com> From: Waiman Long Organization: Red Hat Message-ID: <91094cf3-ca5c-3871-2a9d-09864c63bf7b@redhat.com> Date: Mon, 27 Nov 2017 16:47:16 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <20171127214232.GT983427@devbig577.frc2.facebook.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 27 Nov 2017 21:47:18 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/27/2017 04:42 PM, Tejun Heo wrote: > Hello, Waiman. > > On Mon, Nov 27, 2017 at 04:19:57PM -0500, Waiman Long wrote: >>> Let's start just with [e]cpus and [e]mems. The flags interface looks >>> fine but the implementations of these features are really bad and >>> cgroup2 doesn't migrate resources for other controllers either anyway. >> That is added because the mem_migrate feature is used in libvirt, I >> think. I am thinking of add a "[EXPERIMENTAL]" tag to the flags to >> indicate that it is subject to change. > I see. Do you happen to know what it's used for and why that's > necessary just so that we can evaluate it better? I'm not quite sure > what adding [EXPERIMENTAL] tag would achieve. If we expose the > feature and people use it, we just have to keep it anyway. The mem_migrate feature will probably enforce better NUMA locality as the vCPU may move from one physical CPU to another if it is not pinned. I want to add the experimental tag more in the sense that we are going to add to the list of the flags in the future than removing an existing one. Well, I guess we can just say it in the text instead of adding a tag. Cheers, Longman