This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


RE: [Xen-devel] spurious interrupts

To: "Stephen C. Tweedie" <sct@xxxxxxxxxx>, "Jan Beulich" <jbeulich@xxxxxxxxxx>
Subject: RE: [Xen-devel] spurious interrupts
From: "Deuskar, Prafulla" <prafulla.deuskar@xxxxxxxxx>
Date: Wed, 12 Apr 2006 15:11:41 -0700
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Wed, 12 Apr 2006 15:12:08 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcZedn92Nv72hknGQ22jIefTQ3tPNAABvpLQ
Thread-topic: [Xen-devel] spurious interrupts
>On Wed, 2006-04-12 at 13:48 -0400, Stephen C. Tweedie wrote:
>> > While I haven't heard anything whether others were able to
>> > this, I was now able to nail this down to a simple operation: On
>> > system I'm testing with I was able to identify that the handling of
>> > the interrupt from the SCSI controller triggers a simultaneous
>> > interrupt from one of the USB controllers
>Turns out that I'm seeing the same.  On the box that was showing
>>         irq 16: nobody cared
>>          Disabling IRQ #16
>it seems that the irq16 is indeed getting dispatched every time an
>interrupt arrives for the disk.  In this case it's sata, ICH5 on irq17.
>> (At least, at the time of writing that box is showing only
>> at 15,000 interrupts on irq16 after an hour instead of 100,000 after
>> minutes
>this turned out to be related to disk activity, and a heavy disk load
>rapidly reproduced the problem even with the latest Xen kernel.

We see similar behavior with network traffic - irq16 (attached to USB)
getting dispatched every time NIC interrupt is triggered.


Xen-devel mailing list

<Prev in Thread] Current Thread [Next in Thread>