From: Todd Vierling (no email)
Date: Mon Apr 03 2006 - 09:25:40 EDT
On Sat, 1 Apr 2006, David Lesher wrote:
> Panix is offering Xen-based virtual servers. I mention same here
> only because I've seen almost no discussion of virtualized servers,
> and hope to learn from the surely-resulting flameware....
>
> http://www.panix.com/corp/virtuals/
Xen and similar solutions are gaining popularity because they work on a
similar model as that used for ADSL: most users don't use all the resources
all the time. By virtualizing, the provider can offer "dedicated
colocation" at a somewhat lower cost to the user, and a *much* lower cost to
the provider. If properly provisioned, by distributing more heavily loaded
virtual machines appropriately, you can probably attain virtualization of
20-30 or more per 2-way or 2-dual-core SMP box and still have CPU left over.
Note that Xen in particular has major advantages over some similar products
because it eliminates CPU-consuming system trap hackery needed to emulate
hardware devices and page-table mappings. Xen is not, however, backed with
extensive commercial support (XenSource is still evolving at the moment),
lacks easy integration into popular UI/control-panel products, and requires
special kernels for the contained OS's (not such a big deal in practice).
The current problems haven't stopped some early adopters from trying out
Xen. By and large, those who were once using UML[*] and have now tried Xen
have switched and not looked back.
[*] User Mode Linux, which I went out of my way to heckle (with technically
sound arguments, mind you) at an IETF when it was proposed as a method
of virtualization. The sad part is, some folks bought the drivel and
actually set up businesses using UML as a virtualization layer.
-- -- Todd Vierling <> <> <>
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