From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chuck Ebbert Subject: Re: controlling ACPI IRQ routing Date: Tue, 08 Jan 2008 11:49:05 -0500 Message-ID: <4783A981.9060003@redhat.com> References: <47742083.5060903@howardsilvan.com> <47769494.3080503@howardsilvan.com> <20080102151142.73362648@citycable.ch> <200801050051.20947.lenb@kernel.org> <478103EA.6070503@howardsilvan.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mx1.redhat.com ([66.187.233.31]:56238 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752093AbYAHQtj (ORCPT ); Tue, 8 Jan 2008 11:49:39 -0500 In-Reply-To: <478103EA.6070503@howardsilvan.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Lee Howard Cc: Len Brown , linux-acpi@vger.kernel.org On 01/06/2008 11:38 AM, Lee Howard wrote: > Len Brown wrote: >> On Wednesday 02 January 2008 09:11, Dominique Michel wrote: >> =20 >>> Le Sat, 29 Dec 2007 10:40:20 -0800, >>> Lee Howard a =C3=A9crit : >>> >>> >>> =20 >>>> # cat /proc/interrupts >>>> CPU0 0: 1051464247 IO-APIC-edge timer >>>> 1: 8 IO-APIC-edge i8042 >>>> 8: 0 IO-APIC-edge rtc >>>> 9: 0 IO-APIC-fasteoi acpi >>>> 12: 104 IO-APIC-edge i8042 >>>> 14: 9414304 IO-APIC-edge ide0 >>>> 16: 1051172722 IO-APIC-fasteoi wct4xxp >>>> 19: 1 IO-APIC-fasteoi eth1 >>>> 21: 158008518 IO-APIC-fasteoi eth0 >>>> 22: 6974044 IO-APIC-fasteoi libata >>>> 23: 7071112 IO-APIC-fasteoi libata >>>> NMI: 0 >>>> LOC: 1051371544 >>>> ERR: 0 >>>> >>>> >>>> =20 >>> Based on that, you may want to use rtirq. It is a boot script (need >>> schedutils >>> as dependency) with associated config scripts. >>> http://alsa.opensrc.org/Rtirq >>> >>> In /etc/conf.d/rtirq, you will find: >>> >>> # IRQ thread service names >>> # (space separated list, from higher to lower priority). >>> RTIRQ_NAME_LIST=3D"rtc snd usb i8042" >>> >>> The most important things is that the devices listed here doesn't >>> have any >>> shared IRQ with some other device and that the rtc remain the first >>> listed >>> device (the one with the higer priority), or the system will hang >>> soon or later. >>> >>> This setup is for audio workstation but is very easy to adapt to an= y >>> kind of >>> work. >>> >>> =20 >> >> I've got no experience with the thread priority thing above. >> However, the better way to handle quality of service contention >> is to not do the things you don't care about. >> >> Does the system really need HZ=3D1000? you could slow that down to = 100, >> or run CONFIG_NO_HZ to reduce it even more... >> Also, on a UP, the LAPIC timer interrupt is redundant -- >> you could build your kernel w/o APIC support or boot with nolapic. >> >> This would get rid of the only interrupts which are frequent >> enough to be competing with the device, clock ticks. >=20 > If I boot with nolapic then XT-PIC is used, and the wcfxo device ends= up > sharing an IRQ with libata which results in worse performance than wi= th > it the way that it is. >=20 Try nolapic_timer ? - To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html