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-users

RE: [Xen-users] Slow windows network with gplpv driver.

To: "John McMonagle" <johnm@xxxxxxxxxxx>, "xen-users" <xen-users@xxxxxxxxxxxxxxxxxxx>
Subject: RE: [Xen-users] Slow windows network with gplpv driver.
From: "James Harper" <james.harper@xxxxxxxxxxxxxxxx>
Date: Fri, 4 Mar 2011 10:57:21 +1100
Cc:
Delivery-date: Thu, 03 Mar 2011 15:59:03 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <201103031659.33950.johnm@xxxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <201103031659.33950.johnm@xxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcvZ90VsE1mKRxUhToWpfM4JFLkKDgABs0Bw
Thread-topic: [Xen-users] Slow windows network with gplpv driver.
> 
> This concerns an old problem
>
http://lists.xensource.com/archives/html/xen-users/2010-08/msg00567.html
> 
> Still having the problem with network performance but need to really
fix it.
> 
> Just did a test with 32 bit xp with 0.11.0.238 drive.
> it show device as Xen Net device driver.
> 
> Iperf gives 14.7 Mbits/sec
> 
> Running an xp live boot cd  get 13.6 Mbits/sec
> Doesn't looks like the the pv driver is doing anything to help the
network as
> there is probably extra load with no pv drivers for disk and display.
> 
> How much of a speed improvement are others seeing?
> 
> The real issue is speed for samba shares.
> 
> I have tried on other hardware and it's a bit faster but not that
impressive.
> To keep the speed in perspective this is /proc/cpuinfo
> 

XP is probably a poor benchmark for GPLPV (or even without) for a few
reasons. If you want to get decent performance out of XP, disable the
firewall service (in services, not just in the network control panel)
and append " /PATCHTPR" to the boot.ini entry if using GPLPV. The
problem with XP is that it makes _very_ frequent calls to change and
read the TPR (Task PRiority) register, which incurs quite a bit of
overhead. "/PATCHTPR" avoids that completely on AMD hardware and
optimises the read case on Intel hardware, although I think Intel under
Xen may not suffer so badly these days.

I'm seeing a few gigabits per second when doing DomU<->Dom0 testing, and
full hardware speeds when talking over a physical network adapter when I
last tested.

James


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