Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753608AbcK0VNl (ORCPT ); Sun, 27 Nov 2016 16:13:41 -0500 Received: from mail-wm0-f67.google.com ([74.125.82.67]:36393 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752060AbcK0VNb (ORCPT ); Sun, 27 Nov 2016 16:13:31 -0500 Subject: Re: RFC: documentation of the autogroup feature To: Mike Galbraith References: <41d802dc-873a-ff02-17ff-93ce50f3e925@gmail.com> <1479901185.4306.38.camel@gmx.de> <327586fa-4672-d070-0ded-850654586273@gmail.com> <1479915229.4306.106.camel@gmx.de> Cc: mtk.manpages@gmail.com, Peter Zijlstra , Ingo Molnar , linux-man , lkml , Thomas Gleixner From: "Michael Kerrisk (man-pages)" Message-ID: <8614679c-b1d3-3b35-193d-2ab6eac45aff@gmail.com> Date: Sun, 27 Nov 2016 22:13:26 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1479915229.4306.106.camel@gmx.de> Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1145 Lines: 37 Hi Mike, On 11/23/2016 04:33 PM, Mike Galbraith wrote: > On Wed, 2016-11-23 at 14:54 +0100, Michael Kerrisk (man-pages) wrote: >> Hi Mike, [...] >> Actually, can you define for me what the root task group is, and >> why it exists? That may be worth some words in this man page. > > I don't think we need group scheduling details, there's plenty of > documentation elsewhere for those who want theory. Autogroup is for > those who don't want to have to care (which is also why it should have > never grown nice knob). Actually, the more I think about this, the more I think we *do* need a few details on group scheduling. Otherwise, it's difficult to explain to the use why nice(1) no longer works as traditionally expected. Here's my attempt to define the root task group: * If autogrouping is disabled, then all processes in the root CPU cgroup form a scheduling group (sometimes called the "root task group"). Can you improve on this? Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/