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-users] Difference between xenified and pv_ops kernel

To: Peter Braun <xenware@xxxxxxxxx>
Subject: Re: [Xen-users] Difference between xenified and pv_ops kernel
From: Pasi Kärkkäinen <pasik@xxxxxx>
Date: Mon, 17 Aug 2009 19:11:06 +0300
Cc: Xen List <xen-users@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Mon, 17 Aug 2009 09:11:46 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <acbf498f0908170805y1761c4a1hd618bbb077603421@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/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: <acbf498f0908170805y1761c4a1hd618bbb077603421@xxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.13 (2006-08-11)
On Mon, Aug 17, 2009 at 05:05:56PM +0200, Peter Braun wrote:
> Hi,
> we have successfully tried to run both xenified and pv_ops 2.6.30
> kernels for DomU.
> How would you describe the main difference between those two approaches?
> What is the main difference?
> Are the possibilities the same?
> What about speed?
> Our needs for domu are pretty low - some CPU, some RAM, lvm HDD, 1-3
> virtual NICs. That's all.
> Nothing like PCI/USB passtrough - just plain VPS linux machine.
> Differences from our point of view:
> 1) pv_ops can be used even with latest 2.6.31-rcX kernels

pv_ops Xen domU support has been there since Linux 2.6.24, and like you
said, it is included in the upstream/mainline Linux kernel, so it's always
there to use without extra patches.

Also with pv_ops the same kernel image can be used on baremetal (without
Xen), and also as Xen domU.

> 2) xenified kernel currently with only

Yes it's separate patching, and custom forward-porting, so pv_ops is much
easier solution.

> 3) in XM TOP idling VPS with xenified kernel is really not consuming
> CPU(secs) while
>     VPS with pv_ops kernel is always using like 1-3% of CPU even when
> guest OS idle.

-- Pasi

Xen-users mailing list

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