Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761011AbXERENA (ORCPT ); Fri, 18 May 2007 00:13:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756548AbXEREMy (ORCPT ); Fri, 18 May 2007 00:12:54 -0400 Received: from holomorphy.com ([66.93.40.71]:38301 "EHLO holomorphy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755726AbXEREMx (ORCPT ); Fri, 18 May 2007 00:12:53 -0400 Date: Thu, 17 May 2007 21:13:09 -0700 From: William Lee Irwin III To: Bill Huey Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Linus Torvalds , Andrew Morton , Con Kolivas , Nick Piggin , Mike Galbraith , Arjan van de Ven , Peter Williams , Thomas Gleixner , caglar@pardus.org.tr, Willy Tarreau , Gene Heskett , Mark Lord Subject: Re: [patch] CFS scheduler, -v12 Message-ID: <20070518041309.GA19966@holomorphy.com> References: <20070513153853.GA19846@elte.hu> <20070518001841.GA21140@gnuppy.monkey.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070518001841.GA21140@gnuppy.monkey.org> Organization: The Domain of Holomorphy User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1459 Lines: 28 On Sun, May 13, 2007 at 05:38:53PM +0200, Ingo Molnar wrote: >> So i've added a yield workaround to -v12, which makes it work similar to >> how the vanilla scheduler and SD does it. (Xorg has been notified and >> this bug should be fixed there too. This took some time to debug because >> the 3D driver i'm using for testing does not use sys_sched_yield().) The >> workaround is activated by default so -v12 should work 'out of the box'. On Thu, May 17, 2007 at 05:18:41PM -0700, Bill Huey wrote: > This is an incorrect analysis. OpenGL has the ability to "yield" after > every frame specifically for SGI IRIX (React/Pro) frame scheduler (driven > by the system vertical retrace interrupt) so that it can free up CPU > resources for other tasks to run. The problem here is that the yield > behavior is treated generally instead of specifically to a particular > proportion scheduler policy. > The correct solution is for the app to use a directed yield and a policy > that can directly support it so that OpenGL can guaratee a frame rate > governed by CPU bandwidth allocated by the scheduler. > Will is working on such a mechanism now. What? AFAIK the CFS patches already implement directed yields. -- wli - 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/