From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761274AbYB1RsX (ORCPT ); Thu, 28 Feb 2008 12:48:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754189AbYB1RsO (ORCPT ); Thu, 28 Feb 2008 12:48:14 -0500 Received: from wolverine01.qualcomm.com ([199.106.114.254]:1434 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754008AbYB1RsN (ORCPT ); Thu, 28 Feb 2008 12:48:13 -0500 X-IronPort-AV: E=McAfee;i="5200,2160,5240"; a="979321" Message-ID: <47C6F3DB.8070309@qualcomm.com> Date: Thu, 28 Feb 2008 09:48:11 -0800 From: Max Krasnyanskiy User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Ingo Molnar CC: Peter Zijlstra , Thomas Gleixner , Oleg Nesterov , Steven Rostedt , Paul Jackson , linux-kernel@vger.kernel.org Subject: Re: [RFC/PATCH 0/4] CPUSET driven CPU isolation References: <20080227222103.673194000@chello.nl> <20080228075010.GA28781@elte.hu> In-Reply-To: <20080228075010.GA28781@elte.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote: > * Peter Zijlstra wrote: > >> My vision on the direction we should take wrt cpu isolation. >> >> Next on the list would be figuring out a nice solution to the >> workqueue flush issue. > > nice work Peter, i find this "system sets" extension to cpusets a much > more elegant (and much more future-proof) solution than the proposed > spreadout of the limited hack of isolcpus/cpu_isolated_map. It > concentrates us on a single API and on a single mechanism to handle > isolation matters. (be that for clustering/supercomputing or real-time > purposes) Come on Ingo. You make it sounds like it's radically different solution. At the end of the day we have a bitmap that represents which CPUs can be used for the kernel stuff. How is that different ? I was saying all along that cpusets is a higher level API and was discussing or trying to discuss (people were ignoring my questions) ways to integrate it. > Thanks for insisting on using cpusets for this! > > i've queued up your patches in sched-devel.git, and lets make sure this > has no side-effects on existing functionality. (it shouldnt) Hmm, that was easy. Not a single ack. Even the core part is not complete yet. I pointed out several issues. Like the fact that it does not provide full isolation because it does not move timers, does not handle workqueues. I did not even get a chance to test this stuff properly and see if it actually solves the usecase I was solving with my patches. _Obviously_ we could not have taken my tested solution and evolved it in the direction people wanted to see it evolve, ie integration with the cpusets :(. My main concern is that it introduces a whole new set of notifiers that perform similar functions to what CPU hotplut already does. Max