From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263673AbTDTSnF (ORCPT ); Sun, 20 Apr 2003 14:43:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263674AbTDTSnF (ORCPT ); Sun, 20 Apr 2003 14:43:05 -0400 Received: from zork.zork.net ([66.92.188.166]:60139 "EHLO zork.zork.net") by vger.kernel.org with ESMTP id S263673AbTDTSnC (ORCPT ); Sun, 20 Apr 2003 14:43:02 -0400 To: linux-kernel@vger.kernel.org Subject: Re: irq balancing; kernel vs. userspace From: Sean Neakums X-Worst-Pick-Up-Line-Ever: "Hey baby, wanna peer with my leafnode instance?" X-Message-Flag: Message text advisory: PRURIENT SUBTEXT, ADULT LANGUAGE/SITUATIONS X-Mailer: Norman X-Groin-Mounted-Steering-Wheel: "Arrrr... it's driving me nuts!" X-Alameda: WHY DOESN'T ANYONE KNOW ABOUT ALAMEDA? IT'S RIGHT NEXT TO OAKLAND!!! Organization: The Emadonics Institute Mail-Followup-To: linux-kernel@vger.kernel.org Date: Sun, 20 Apr 2003 19:55:03 +0100 In-Reply-To: <1050863476.1412.11.camel@laptop.fenrus.com> (Arjan van de Ven's message of "20 Apr 2003 20:31:16 +0200") Message-ID: <6ur87xkni0.fsf@zork.zork.net> User-Agent: Gnus/5.090019 (Oort Gnus v0.19) Emacs/21.2 (gnu/linux) References: <6uwuhpl2u5.fsf@zork.zork.net> <1050863476.1412.11.camel@laptop.fenrus.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Arjan van de Ven writes: > On Sun, 2003-04-20 at 15:23, Sean Neakums wrote: >> I thought I'd play with the userspace IRQ-balancer, but booting with >> noirqbalance seems not to not balance. Possibly I misunderstand how >> this all fits together. > > this looks like you haven't started the userspace daemon (yet) I just cranked it up, and now I see: $ cat /proc/interrupts CPU0 CPU1 0: 9627420 12189635 IO-APIC-edge timer 1: 4165 4347 IO-APIC-edge i8042 2: 0 0 XT-PIC cascade 4: 282749 315988 IO-APIC-edge serial 8: 2 1 IO-APIC-edge rtc 9: 3 2 IO-APIC-level eth1 10: 19270 20109 IO-APIC-level via82cxxx, eth0 11: 34913 19457 IO-APIC-level aic7xxx 12: 8777 8835 IO-APIC-edge i8042 NMI: 0 0 LOC: 21817495 21817494 ERR: 0 MIS: 0 I was confused at first because I was thinking of IRQ balancing as balancing IRQs *across* CPUs. This kind of balancing seems to be about spreading IRQ *sources* across CPUs. I guess it's good for caches and whatnot for IRQs to be consistently serviced by the same CPU. Anyway, it seems to be working. Thanks! -- Sean Neakums -