From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754169AbaDFIae (ORCPT ); Sun, 6 Apr 2014 04:30:34 -0400 Received: from mail-we0-f182.google.com ([74.125.82.182]:61098 "EHLO mail-we0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753629AbaDFIaZ (ORCPT ); Sun, 6 Apr 2014 04:30:25 -0400 Message-ID: <1396773020.11763.17.camel@marge.simpson.net> Subject: Re: [PATCH V2 0/8] cpusets: Isolate CPUs via sysfs using cpusets From: Mike Galbraith To: Viresh Kumar Cc: tglx@linutronix.de, fweisbec@gmail.com, peterz@infradead.org, mingo@kernel.org, tj@kernel.org, lizefan@huawei.com, linaro-kernel@lists.linaro.org, linaro-networking@linaro.org, Arvind.Chauhan@arm.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Date: Sun, 06 Apr 2014 10:30:20 +0200 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2014-04-04 at 14:05 +0530, Viresh Kumar wrote: > We need to migrate away all the background kernel activities (Unbound) for > systems requiring isolation of cores (HPC, Real time, networking, etc). After > creating cpusets, you can write 1 or 0 to cpuset.quiesce file. I wonder if adding a quiesce switch is really necessary. Seems to me that if you don't have load balancing turned off, you can't be very concerned about perturbation, so this should be tied into the load balancing on/off switch as an extension to isolating cores from the #1 perturbation source, the scheduler. I also didn't notice a check for is_cpu_exclusive() at a glance, which would be a bug, but one that would go away if this additional isolation were coupled to the existing isolation switch. -Mike