Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752881AbYLPG4R (ORCPT ); Tue, 16 Dec 2008 01:56:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751158AbYLPG4E (ORCPT ); Tue, 16 Dec 2008 01:56:04 -0500 Received: from viefep15-int.chello.at ([62.179.121.35]:52122 "EHLO viefep18-int.chello.at" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750875AbYLPG4C (ORCPT ); Tue, 16 Dec 2008 01:56:02 -0500 X-SourceIP: 213.46.9.244 Subject: Re: [Bug #12208] uml is very slow on 2.6.28 host From: Peter Zijlstra To: Miklos Szeredi Cc: rjw@sisk.pl, efault@gmx.de, mingo@elte.hu, linux-kernel@vger.kernel.org, kernel-testers@vger.kernel.org In-Reply-To: References: Content-Type: text/plain Date: Tue, 16 Dec 2008 07:56:01 +0100 Message-Id: <1229410561.14605.42.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.24.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1474 Lines: 33 On Tue, 2008-12-16 at 01:49 +0100, Miklos Szeredi wrote: > On Sat, 13 Dec 2008, Rafael J. Wysocki wrote: > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12208 > > Subject : uml is very slow on 2.6.28 host > > Submitter : Miklos Szeredi > > Date : 2008-12-12 9:35 (2 days old) > > References : http://marc.info/?l=linux-kernel&m=122907463518593&w=4 > > I did a bisection, and this is the commit which is responsible: > > commit 464b75273f64be7c81fee975bd6ca9593df3427b > Author: Peter Zijlstra > Date: Fri Oct 24 11:06:15 2008 +0200 > > sched: re-instate vruntime based wakeup preemption > > The advantage is that vruntime based wakeup preemption has a better > conceptual model. Here wakeup_gran = 0 means: preempt when 'fair'. > Therefore wakeup_gran is the granularity of unfairness we allow in order > to make progress. > > Signed-off-by: Peter Zijlstra > Acked-by: Mike Galbraith > Signed-off-by: Ingo Molnar How's 27? That code basically makes .28 do what .27 did, we tried something else for a little while and that made stuff suck rocks. -- 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/