From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [Fwd: Re: RFC for a new Scheduling policy/class in the Linux-kernel] Date: Mon, 03 May 2010 16:41:22 +0200 Message-ID: <1272897682.1642.124.camel@laptop> References: <20100426115658.GA21346@cs.fsu.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: raj@ece.cmu.edu, jayhawk@soe.ucsc.edu, raistlin@linux.it, niehaus@ittc.ku.edu, henrik@austad.us, linux-kernel@vger.kernel.org, mingo@elte.hu, billh@gnuppy.monkey.org, linux-rt-users@vger.kernel.org, fabio@gandalf.sssup.it, anderson@cs.unc.edu, tglx@linutronix.de, dhaval.giani@gmail.com, cucinotta@sssup.it, lipari@retis.sssup.it, baker.tlh@comcast.net To: Ted Baker Return-path: In-Reply-To: <20100426115658.GA21346@cs.fsu.edu> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org Hi Ted, On Mon, 2010-04-26 at 07:56 -0400, Ted Baker wrote: > I have not seen any more e-mail on this. How is it going? Is there any > chance of rolling in some corrections for the SCHED_SPORADIC treatment? In > particular, could we have a DO_NOT_RUN priority, that is guaranteed to > prevent a task from running at all? Without having fully read the referenced paper, we're currently looking to support the sporadic task model through SCHED_DEADLINE (by our SSSUP friends): http://lkml.org/lkml/2010/2/28/107 This work aims to implement a full sporadic task scheduler [initially (g)EDF], SCHED_SPORADIC would have been a better name, but since POSIX stole that from us we took SCHED_DEADLINE to indicate its a deadline scheduler. Along with this work comes the full Deadline-inheritance (which should be but a small change from our current Priority-inheritance code), and also Bandwidth-inheritance (more work). Esp. the latter would also be required for your proposed SCHED_SPORADIC since it does aim to be a 'strict' bandwidth enforcing scheduler. [Does the proposed 'fixed' SCHED_SPORADIC deal with admission control?] But as it stands, this work would provide much more complete sporadic task support than the fixed SCHED_SPORADIC would.