Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755081AbaAUPqg (ORCPT ); Tue, 21 Jan 2014 10:46:36 -0500 Received: from merlin.infradead.org ([205.233.59.134]:58640 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754532AbaAUPqe (ORCPT ); Tue, 21 Jan 2014 10:46:34 -0500 Date: Tue, 21 Jan 2014 16:46:03 +0100 From: Peter Zijlstra To: Michael Kerrisk Cc: Dario Faggioli , Thomas Gleixner , Ingo Molnar , rostedt@goodmis.org, Oleg Nesterov , fweisbec@gmail.com, darren@dvhart.com, johan.eker@ericsson.com, p.faure@akatech.ch, Linux Kernel , claudio@evidence.eu.com, michael@amarulasolutions.com, fchecconi@gmail.com, tommaso.cucinotta@sssup.it, juri.lelli@gmail.com, nicola.manica@disi.unitn.it, luca.abeni@unitn.it, dhaval.giani@gmail.com, hgu1972@gmail.com, Paul McKenney , insop.song@gmail.com, liming.wang@windriver.com, jkacur@redhat.com Subject: Re: [PATCH 01/13] sched: Add 3 new scheduler syscalls to support an extended scheduling parameters ABI Message-ID: <20140121154603.GF3694@twins.programming.kicks-ass.net> References: <20131217122720.950475833@infradead.org> <20131217123352.692059839@infradead.org> <20140121153851.GZ31570@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140121153851.GZ31570@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 21, 2014 at 04:38:51PM +0100, Peter Zijlstra wrote: > SCHED_DEADLINE: Sporadic task model deadline scheduling > SCHED_DEADLINE is an implementation of GEDF (Global Earliest > Deadline First) with additional CBS (Constant Bandwidth Server). We might want to re-word that to: SCHED_DEADLINE currently is an implementation of GEDF, however any policy that correctly schedules the sporadic task model is a valid implementation. To make sure we should not rely on the actual implementation; there's many possible algorithms to schedule the sporadic task model. > The CBS guarantees that tasks that over-run their specified > budget are throttled and do not affect the correct performance > of other SCHED_DEADLINE tasks. > > SCHED_DEADLINE tasks will fail FORK(2) with -EAGAIN > > Setting SCHED_DEADLINE can fail with -EINVAL when admission > control tests fail. > -- 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/