Re: some questions

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Thu, Jan 05, 2006 at 10:15:52AM +0200, Mihai CHELARU wrote:
> Hello Sirs,
> 
> I buying a new server in a couple of days and I want to know if it's possible 
> to do the following things (I'll use xen2 and netbsd3 as both dom0 and all 
> domUs):
> 
> 1) the server will be SMP with HT processors. is it possible to keep each 
> domU on a physical CPU and each domU to use also HT (shorlty, every VM 
> grounded to a physical CPU, while the kernel should see the 2 HT processors 
> somehow) ?

Not with Xen2. Xen2 doens't suppport SMP in guests. Xen3 does but a lot of
work is needed in NetBSD/Xen to support SMP.

> 2) Even more, is it possible to link every VM to a virtual HT processor ?

Yes

> Should I be aware of any security issues in this case ?.

You're talking about the timing attack via the shared cache ? It's probably
possible between 2 guests, but probably harder than on a SMP system because
it's harder to get information from one guest about the other (like, what
processes are currently running)

> 3) if the server will have 2 PCI SCSI controllers is it possible to use each 
> one for single machine (shortly, domU1 should see and use only the first 
> controller and use it's attached disks, and domU2 the second..) ? 
> physdev_dom0_hide should do the trick, right ?

Yes, that what's it's for. You'll have to build custom kernels with PCI support
for the domUs

> 4) is it possible to use ALTQ in xen0 kernel in order to limit the 
> unprivileged domains ?

Yes, to a limited extent. I have plans to improve this, but there's already
so much on my todo list ...

> 5) is it possible to fix the xen networking interface names corresponding to 
> each domU ?

Unfortunably not.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--