Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932553AbXK2Q0a (ORCPT ); Thu, 29 Nov 2007 11:26:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932451AbXK2Q0T (ORCPT ); Thu, 29 Nov 2007 11:26:19 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:60201 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932398AbXK2Q0S (ORCPT ); Thu, 29 Nov 2007 11:26:18 -0500 Date: Thu, 29 Nov 2007 17:25:56 +0100 From: Ingo Molnar To: Miklos Szeredi Cc: jdike@addtoit.com, user-mode-linux-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: scheduling anomaly on uml (was: -rt doesn't compile for UML) Message-ID: <20071129162556.GA4268@elte.hu> References: <20071128150637.GA5518@c2.user-mode-linux.org> <20071128182935.GA8048@c2.user-mode-linux.org> <20071129105744.GI10577@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 850 Lines: 23 * Miklos Szeredi wrote: > > to get symbolic stack backdumps for the wakeup points, and add > > trace_special_sym() calls to generate extra stackdump entries at > > arbitrary places. schedule() does not have it right now - it might > > make sense to add it. > > OK, this helped. > > It looks like the delays are caused by the page allocator, and not > UML. Which is good news, because I'm supposed to understand memory > management better than scheduling. heh :-) Scheduling isnt hard either - and looking at traces (especially with mcount_enabled=1) certainly helps. Ingo - 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/