From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757181AbZHZH3t (ORCPT ); Wed, 26 Aug 2009 03:29:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757106AbZHZH3t (ORCPT ); Wed, 26 Aug 2009 03:29:49 -0400 Received: from mail-bw0-f219.google.com ([209.85.218.219]:50198 "EHLO mail-bw0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757101AbZHZH3r (ORCPT ); Wed, 26 Aug 2009 03:29:47 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=BbxFps5ubQh/o/ZH5Z3MCWHeeWgq/QcWN+zkKibo59PYlETPbdbmXoBr91KUx5v8Hs g5ag686ckel1wFWkdL21H+BCZ3C8YbrfmL0uAPe7P69oBPTnNr5joWF+4YkdPMkBFy2/ YwKjpQ8HWkM7I+SFanTZpGF38wRszh6bx6BXc= Subject: Re: RFC: THE OFFLINE SCHEDULER From: raz ben yehuda To: Peter Zijlstra Cc: Chris Friesen , Christoph Lameter , Mike Galbraith , riel@redhat.com, mingo@elte.hu, andrew motron , wiseman@macs.biu.ac.il, lkml , linux-rt-users@vger.kernel.org In-Reply-To: <1251264700.7538.1178.camel@twins> References: <1250983671.5688.21.camel@raz> <1251004897.7043.70.camel@marge.simson.net> <1251018551.3810.35.camel@raz> <1251012621.14003.71.camel@marge.simson.net> <1251025557.3810.65.camel@raz> <1251021133.14003.172.camel@marge.simson.net> <1251222993.7023.53.camel@marge.simson.net> <1251227322.7538.1172.camel@twins> <4A943A00.9080609@nortel.com> <1251264700.7538.1178.camel@twins> Content-Type: text/plain Date: Wed, 26 Aug 2009 13:29:58 +0300 Message-Id: <1251282598.3514.20.camel@raz> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-8.el5_2.3) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2009-08-26 at 07:31 +0200, Peter Zijlstra wrote: > On Tue, 2009-08-25 at 13:22 -0600, Chris Friesen wrote: > > On 08/25/2009 01:08 PM, Peter Zijlstra wrote: > > > > > Christoph, stop being silly, this offline scheduler thing won't happen, > > > full stop. > > > > > > Its not a maintainable solution, it doesn't integrate with existing > > > kernel infrastructure, and its plain ugly. > > > > > > If you want something work within Linux, don't build kernels in kernels > > > or other such ugly hacks. > > > > Is it the whole concept of isolating one or more cpus from all normal > > kernel tasks that you don't like, or just this particular implementation? > > > > I ask because I know of at least one project that would have used this > > capability had it been available. As it stands they have to live with > > the usual kernel threads running on the cpu that they're trying to > > dedicate to their app. > > Its the simple fact of going around the kernel instead of using the > kernel. > > Going around the kernel doesn't benefit anybody, least of all Linux. > > So its the concept of running stuff on a CPU outside of Linux that I > don't like. I mean, if you want that, go ahead and run RTLinux, RTAI, > L4-Linux etc.. lots of special non-Linux hypervisor/exo-kernel like > things around for you to run things outside Linux with. Hello Peter, Hello All. First , It a pleasure seeing that you take interest in OFFSCHED. So thank you. To my opinion this a matter of defining what a system is. Queuing theory teaches us that a system is defined to be everything within the boundary of the computer, this includes, peripherals, processors, RAM , operating system, the distribution and so on. The kernel is merely a part of the SYSTEM, it is not THE SYSTEM; and it is not a blasphemy to bypass it.The kernel is not the goal and it is not sacred. OFFSCHED is bad name to my project. My project is called SOS = Service Oriented System. SOS, has nothing to do with Real time. SOS is about arranging the processors to serve the SYSTEM the best way we can; if the kernel disturbs the service, put it a side I say. How will the kernel is going to handle 32 processors machines ? These numbers are no longer a science-fiction. What i am suggesting is merely a different approach of how to handle multiple core systems. instead of thinking in processes, threads and so on i am thinking in services. Why not take a processor and define this processor to do just firewalling ? encryption ? routing ? transmission ? video processing... and so on... Raz