WARNING - OLD ARCHIVES

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/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] theoretical network rx performance of Windows with PV dr

To: James Harper <james.harper@xxxxxxxxxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] theoretical network rx performance of Windows with PV drivers
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Tue, 18 Nov 2008 12:47:01 +0000
Cc:
Delivery-date: Tue, 18 Nov 2008 04:47:27 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <AEC6C66638C05B468B556EA548C1A77D0154FC0C@trantor>
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/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AclJdZaq6OGodxhGRNi3MA0h9mpWyQABil1r
Thread-topic: [Xen-devel] theoretical network rx performance of Windows with PV drivers
User-agent: Microsoft-Entourage/11.4.0.080122
On 18/11/08 12:02, "James Harper" <james.harper@xxxxxxxxxxxxxxxx> wrote:

> I'm finding some odd things during development of the GPLPV and am
> wondering if I'm just expecting too much of a HVM Windows DomU.
> 
> I'm using iperf for testing, and the most I can get on a 1.8GHz AMD1210
> out of a Dom0->DomU network performance is about 500MBits, and that's
> with Dom0 sending packets at close to 1GBit, with about 50% of packets
> being lost. But it's not consistent... things seem to stall at strange
> times (some of that may be a driver or a windows problem - the time
> between scheduling a Dpc and the Dpc being executed is up to 3 seconds
> sometimes when this happens...)
> 
> How much overhead is introduced in the event channel -> HVM IRQ path, as
> compared to the normal interdomain event channels? I think that the
> delay there might be bringing me down, but maybe I'm looking in the
> wrong place?

I don't think evtchn->IRQ latency is particularly large. But also I don't
know what else might be causing your erratic behaviour.

 -- Keir



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel