Mailinglist Archive: opensuse (3337 mails)

< Previous Next >
Re: [SLE] xen versu vmware
  • From: Stephen Boddy <stephen.boddy@xxxxxxxxxxxxxx>
  • Date: Sun, 23 Apr 2006 21:02:12 +0100
  • Message-id: <200604232102.12901.stephen.boddy@xxxxxxxxxxxxxx>
On Sunday 23 April 2006 20:31, jdd sur free wrote:
> Hello :-)
>
> I use vmware for testing purpose (for example new 10.1). I
> do this for ages, now (was vmware 2.0)

VMWare (currently) emulates all a new 386 compatible system, but allows the
guest to use the CPU natively. There is some overhead associated with
emulating the system.

> but vmware is dawn slow. Bochs is worst in this respect.

Bochs emulates both the system and the CPU. Much more overhead, much slower.

> Is Xen able to do the same job? I could never understand
> what Xen is good for :-(((

Xen hosts and guests (more properly Priviledged and Unpriviledged Domains) are
specially modified to know they are running under the Xen hypervisor (hence
you can't run Windows). Because of this the host/guest runs natively on the
CPU, and doesn't require the level of system emulation that VMWare does. This
means it runs significantly closer to native speed.

With the new Vanderpool or upcoming Pacifica tech from Intel and AMD
respectively, the host/guest will not need to be modified for Xen manage
them.

Right now, Xen is excellent provided you are in an OSS environment. i.e. an
ISP can offer individual virtual linux machines to customers. They can then
aggregate, manage, and migrate those on large servers, maximising the
resource usage of those machines, and scaling their servers and network in a
controlled manner.

Until Vanderpool and Pacifica are more widely deployed, it's a much tougher
sell for individual users. Traditionally the great feature of VMWare (for me
at least) was the ability to run legacy Windows apps in an OSS system, and no
Wine is frequently not the answer to that conundrum. If I'm limited to OSS in
my guests, then why not just run it on my host? There are cases where it is
useful, i.e. testing environments etc, but it very much depends on your
usage.
--
Steve Boddy

< Previous Next >
References