Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754074Ab3F0VE4 (ORCPT ); Thu, 27 Jun 2013 17:04:56 -0400 Received: from mail-yh0-f50.google.com ([209.85.213.50]:63652 "EHLO mail-yh0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753854Ab3F0VEz (ORCPT ); Thu, 27 Jun 2013 17:04:55 -0400 Date: Thu, 27 Jun 2013 14:04:45 -0700 From: Tejun Heo To: Tim Hockin Cc: Li Zefan , Containers , Cgroups , bsingharora , "dhaval.giani" , Kay Sievers , jpoimboe , "Daniel P. Berrange" , lpoetter , workman-devel , "linux-kernel@vger.kernel.org" , dawnchen@google.com Subject: Re: cgroup: status-quo and userland efforts Message-ID: <20130627210445.GA22860@mtj.dyndns.org> References: <20130625000118.GT1918@mtj.dyndns.org> <20130626212047.GB4536@htj.dyndns.org> <20130627010427.GF4536@htj.dyndns.org> <20130627173809.GB5599@mtj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1915 Lines: 47 Hello, On Thu, Jun 27, 2013 at 01:46:18PM -0700, Tim Hockin wrote: > So what you're saying is that you don't care that this new thing is > less capable than the old thing, despite it having real impact. Sort of. I'm saying, at least up until now, moving away from orthogonal hierarchy support seems to be the right trade-off. It all depends on how you measure how much things are simplified and how heavy the "real impacts" are. It's not like these things can be determined white and black. Given the current situation, I think it's the right call. > If controller C is enabled at level X but disabled at level X/Y, does > that mean that X/Y uses the limits set in X? How about X/Y/Z? Y and Y/Z wouldn't make any difference. Tasks belonging to them would behave as if they belong to X as far as C is concerened. > So take away some of the flexibility that has minimal impact and > maximum return. Splitting threads across cgroups - we use it, but we > could get off that. Force all-or-nothing joining of an aggregate Please do so. > construct (a container vs N cgroups). > > But perform surgery with a scalpel, not a hatchet. As anything else, it's drawing a line in a continuous spectrum of grey. Right now, given that maintaining multiple orthogonal hierarchies while introducing a proper concept of resource container involves addition of completely new constructs and complexity, I don't think that's a good option. If there are problems which can't be resolved / worked around in a reasonable manner, please bring them up along with their contexts. Let's examine them and see whether there are other ways to accomodate them. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/