From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932419AbXBWOpV (ORCPT ); Fri, 23 Feb 2007 09:45:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932429AbXBWOpV (ORCPT ); Fri, 23 Feb 2007 09:45:21 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:43333 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932419AbXBWOpU (ORCPT ); Fri, 23 Feb 2007 09:45:20 -0500 Subject: Re: irq balancing question From: Arjan van de Ven To: Imre Gergely Cc: linux-kernel@vger.kernel.org In-Reply-To: <45DED0D6.1040700@astral.ro> References: <45DED0D6.1040700@astral.ro> Content-Type: text/plain Organization: Intel International BV Date: Fri, 23 Feb 2007 15:45:17 +0100 Message-Id: <1172241917.3241.4.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.8.3 (2.8.3-1.fc6) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2007-02-23 at 13:32 +0200, Imre Gergely wrote: > hi > > i have a SMP with 2x duo-core Opteron processors, and i have an ethernet card > (eth0). i want to balance the interrupts generated by the card to all 4 > processors. you have only one card? then balancing like you say will only really hurt you; neither linux nor the chipset will do this. > is this irq balancing a feature in the chipset, or driver, or kernel ? i got > the idea of the smp_affinity stuff, and i've set it to "f", but nothing > happens, i mean i see only one CPU getting the interrupts. if you have multiple real interrupt sources you can balance between them using irqbalance, see http://www.irqbalance.org But note that this program will NOT move one irq across 4 cpus all the time, since that gives *really* bad performance. -- if you want to mail me at work (you don't), use arjan (at) linux.intel.com Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org