From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753857AbYHKPHm (ORCPT ); Mon, 11 Aug 2008 11:07:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751610AbYHKPHg (ORCPT ); Mon, 11 Aug 2008 11:07:36 -0400 Received: from rgminet01.oracle.com ([148.87.113.118]:38038 "EHLO rgminet01.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751348AbYHKPHf (ORCPT ); Mon, 11 Aug 2008 11:07:35 -0400 Date: Mon, 11 Aug 2008 08:05:45 -0700 From: Randy Dunlap To: Dario Faggioli Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Thomas Gleixner , Steven Rostedt , Andrew Morton , Ulrich Drepper Subject: Re: [RFC 1/1][PATCH] POSIX SCHED_SPORADIC implementation for tasks and groups Message-Id: <20080811080545.d8f42601.randy.dunlap@oracle.com> In-Reply-To: <1218465906.6450.42.camel@Palanthas> References: <1218465906.6450.42.camel@Palanthas> Organization: Oracle Linux Eng. X-Mailer: Sylpheed 2.5.0 (GTK+ 2.12.0; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAQAAAAI= X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Aug 2008 16:45:06 +0200 Dario Faggioli wrote: > diff --git a/init/Kconfig b/init/Kconfig > index b678803..97fbdfc 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -323,6 +323,44 @@ config CPUSETS > config HAVE_UNSTABLE_SCHED_CLOCK > bool > > +config POSIX_SCHED_SPORADIC > + bool "SCHED_SPORADIC POSIX scheduling policy support" > + default n > + help > + Enable the SCHED_SPORADIC POSIX scheduling policy, which mimics > + the behaviour of the Sporadic Server, a well known mechanism > + to schedule aperiodic or sporadic tasks in periodic-based fixed > + priorit real-time systems. priority > + > + To get details about the SCHED_SPORADIC scheduling policy refer to > + "The Open Group Base Specifications Issue 6", IEEE Std 1003.1, > + 2004 Edition. > + > + [http://www.opengroup.org/onlinepubs/009695399/nfindex.html] > + > +config SCHED_SPORADIC_REPL_MAX > + int "Maximum number of pending recharges" > + range 1 1000 > + depends on POSIX_SCHED_SPORADIC > + default 10 > + help > + Let you chose the maximum number of recharges that can be Lets you choose > + pending at a given time instant for a SCHED_SPORADIC task > + (or task group if group scheduling is configured). > + > + The kernel data structure handling the SCHED_SPORADIC scheduling > + policy for tasks and groups contains a buffer of pending > + replenishment this size large. > + For tasks it is dynamically allocated when SCHED_SPORADIC is set > + as the scheduling policy of the task, while for group it is created > + as soon as the group itself is allocated. > + > + Anyway, since this is going to cause some memory overhead, it is > + wise to not set this to a too much high value. wise not to set this to a very high value. // or some other rewording > + The best value depends on the characteristics of the application > + you are going to use, but probably a value from 10 to 20 is > + suitable for the most of the situations. > + > config GROUP_SCHED > bool "Group CPU scheduler" > depends on EXPERIMENTAL --- ~Randy Linux Plumbers Conference, 17-19 September 2008, Portland, Oregon USA http://linuxplumbersconf.org/