Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932566AbWAJWMa (ORCPT ); Tue, 10 Jan 2006 17:12:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932567AbWAJWMa (ORCPT ); Tue, 10 Jan 2006 17:12:30 -0500 Received: from dvhart.com ([64.146.134.43]:14209 "EHLO dvhart.com") by vger.kernel.org with ESMTP id S932566AbWAJWM3 (ORCPT ); Tue, 10 Jan 2006 17:12:29 -0500 Message-ID: <43C4314C.4030800@mbligh.org> Date: Tue, 10 Jan 2006 14:12:28 -0800 From: Martin Bligh User-Agent: Mozilla Thunderbird 1.0.7 (X11/20051011) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Jesper Juhl Cc: Josef Sipek , Linux Kernel Mailing List Subject: Re: Although CONFIG_IRQBALANCE is enabled IRQ's don't seem to be balanced very well References: <9a8748490601100314u26d4a566uc41a1912e410ea46@mail.gmail.com> <20060110203115.GB5479@filer.fsl.cs.sunysb.edu> <43C42708.4020108@mbligh.org> <9a8748490601101410i31a8447ev2bf8fafe570fc407@mail.gmail.com> In-Reply-To: <9a8748490601101410i31a8447ev2bf8fafe570fc407@mail.gmail.com> 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 Content-Length: 1576 Lines: 51 Jesper Juhl wrote: > On 1/10/06, Martin Bligh wrote: > >>Josef Sipek wrote: >> >>>On Tue, Jan 10, 2006 at 12:14:42PM +0100, Jesper Juhl wrote: >>> >>> >>>>Do I need any userspace tools in addition to CONFIG_IRQBALANCE? >>> >>> >>>Last I checked, yes you do need "irqbalance" (at least that's what >>>the package is called in debian. >> >>Nope - you need the kernel option turned on OR the userspace daemon, >>not both. >> > > Ok, good to know. > > >>If you're not generating interrupts at a high enough rate, it won't >>rotate. That's deliberate. >> > > > Hmm, and what would count as "a high enough rate"? > > I just did a small test with thousands of ping -f's through my NIC > while at the same time giving the disk a good workout with tons of > find's, sync's & updatedb's - that sure did drive up the number of > interrupts and my load average went sky high (amazingly the box was > still fairly responsive): > > root@dragon:/home/juhl# uptime > 22:59:58 up 12:43, 1 user, load average: 1015.48, 715.93, 429.07 > > but, not a single interrupt was handled by CPU1, they all went to CPU0. > > Do you have a good way to drive up the nr of interrupts above the > treshhold for balancing? Is it HT? ISTR it was intelligent enough to ignore that. But you'd have to look at the code to be sure. M. - 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/