From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756687AbXIMNl0 (ORCPT ); Thu, 13 Sep 2007 09:41:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754178AbXIMNlS (ORCPT ); Thu, 13 Sep 2007 09:41:18 -0400 Received: from mx1.redhat.com ([66.187.233.31]:59990 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753042AbXIMNlS (ORCPT ); Thu, 13 Sep 2007 09:41:18 -0400 Message-ID: <46E93DDC.7090207@redhat.com> Date: Thu, 13 Sep 2007 09:40:44 -0400 From: Chris Snook User-Agent: Thunderbird 2.0.0.5 (X11/20070719) MIME-Version: 1.0 To: Jesse Barnes CC: Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: Lossy interrupts on x86_64 References: <200709120833.15980.jbarnes@virtuousgeek.org> In-Reply-To: <200709120833.15980.jbarnes@virtuousgeek.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jesse Barnes wrote: > I just narrowed down a weird problem where I was losing more than 50% of > my vblank interrupts to what seems to be the hires timers patch. Stock > 2.6.23-rc5 works fine, but the latest (171) kernel from rawhide drops > most of my interrupts unless I also have another interrupt source > running (e.g. if I hold down a key or move the mouse I get the expected > number of vblank interrupts, otherwise I get between 3 and 30 instead > of the expected 60 per second). > > Any ideas? It seems like it might be bad APIC programming, but I > haven't gone through those mods to look for suspects... What happens if you boot with 'noapic' or 'pci=nomsi'? Please post dmesg as well so we can see how the kernel is initializing the relevant hardware. -- Chris