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] Does VT have any benefits for paravirtualization?

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-users] Does VT have any benefits for paravirtualization?
From: Mark Williamson <mark.williamson@xxxxxxxxxxxx>
Date: Mon, 10 Apr 2006 14:28:06 +0100
Cc: Alexander Dubinin <adubinin@xxxxxxxxx>
Delivery-date: Mon, 10 Apr 2006 06:31:21 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <76e7486b0604081824p9278378x8daf8dbad385775c@xxxxxxxxxxxxxx>
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/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <76e7486b0604081824p9278378x8daf8dbad385775c@xxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: KMail/1.9.1
> Seems like currently VT is used to provide full virtualizaton, but may
> it help somehow for increasing modified OS performance?
>
> As far as I understand, it may improve CPU sharing even for
> para-virtualization, isn't it?

It's not currently used in the paravirtualised case.

In the future we may experiment with exposing varying amounts of the 
paravirtualisation API to a fully virtualised guest through paravirtualised 
drivers.  And conversely, we may use the hypercall transfer page to cause a 
Xen-aware guest to execute a certain amount of hardware-assist rather than 
explicit hypercalls.

Also, there are likely to be some features (tagged TLB, perhaps?) which might 
be leveraged by Xen in the paravirt case, or even by guest OSes (in which 
case we'd need to virtualise that too...!).

Cheers,
Mark

-- 
Dave: Just a question. What use is a unicyle with no seat?  And no pedals!
Mark: To answer a question with a question: What use is a skateboard?
Dave: Skateboards have wheels.
Mark: My wheel has a wheel!

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

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