From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 6 May 2002 14:37:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 6 May 2002 14:37:38 -0400 Received: from e21.nc.us.ibm.com ([32.97.136.227]:31173 "EHLO e21.nc.us.ibm.com") by vger.kernel.org with ESMTP id ; Mon, 6 May 2002 14:37:38 -0400 Date: Mon, 06 May 2002 12:35:41 -0700 From: "Martin J. Bligh" To: Kosta Porotchkin , linux-kernel@vger.kernel.org Subject: Re: Wrong IRQ distribution on Dual Xeon SMP system (2.4.17). Message-ID: <246660000.1020713741@flay> In-Reply-To: <003901c1f532$4116fcc0$a396a8c0@compaq12xl510a> X-Mailer: Mulberry/2.1.2 (Linux/x86) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > Problem: Wrong interrupts distribution between processors, as a result of > IO APIC configuration errors > > Platform: SuperMicro P4DP6 motherboard (Intel E7500 chipset) with two Intel > Xeon Processors (512 Kb L2 cache @ 2.2 GHz), 1 Gb PC2100 RAM. Phoenix BIOS > 1.1a (latest available for this board). Hyper threading enabled, ACPI > enabled. > > Kernel: 2.4.17 Sherman-x330 (MontaVista) - SMP enabled. > > Problem Description: > > After booting the /proc/interrupts files reads as follows: > > CPU0 CPU1 CPU2 CPU3 > 0: 23794 0 0 0 IO-APIC-edge timer > 1: 1900 0 0 0 IO-APIC-edge keyboard > 2: 0 0 0 0 XT-PIC cascade > 4: 0 0 0 0 IO-APIC-edge KGDB-stub > 9: 0 0 0 0 IO-APIC-edge acpi > 17: 4718 0 0 0 IO-APIC-level eth0 > NMI: 23672 23672 23672 23672 > LOC: 23649 23648 23648 23646 > ERR: 0 > MIS: 0 P4 based systems don't round-robin interrupts like P3 based systems do. Check back in the archives, and find one of the interrupt routing patches. Dave Olien had one, and Ingo Molnar had one, they use slightly different approaches. Martin.