Re: FreeBSD HVM guests?

[Hugo Silva <hugo%barafranca.com@localhost>]

Manuel Bouyer wrote:
> On Mon, May 11, 2009 at 04:40:55PM -0400, Steven M. Bellovin wrote:
>   
> > On Mon, 11 May 2009 16:15:46 +0200
> > Manuel Bouyer <bouyer%antioche.eu.org@localhost> wrote:
> >
> >     
> > > On Mon, May 11, 2009 at 02:50:11PM +0100, Hugo Silva wrote:
> > >       
> > > > Hi,
> > > >
> > > > I am considering to install NetBSD 5/Xen (64 bits) on some servers
> > > > that currently run FreeBSD 7/amd64. I've been testing NetBSD/Xen
> > > > i386 on older hardware (no hardware virtualization support) with
> > > > NetBSD PV domU's; It seems to work just fine.
> > > >
> > > > For my purposes, however, I need FreeBSD guests, and I am unable to
> > > > test this at the moment.
> > > >
> > > > I would like to know if anyone has useful feedback regarding HVM
> > > > guests, FreeBSD in particular, and NetBSD/Xen dom0 stability and
> > > > maturity in general.
> > > >         
> > > NetBSD/Xen dom0 is stability is good; I've several servers running it,
> > > with NetBSD PV, linux PV, linux HVM and windows HVM guests. No
> > > problems so far.
> > >
> > > I would expect a FreeBSD HVM guest to run just fine; it will see a
> > > PIIX3 IDE controller and a ne2000 ethernet device. Be aware that
> > > I/O performances won't be great using these emulated device though;
> > > but if your FreeBSD guest doesn't do mych I/O it should be fine.
> > >
> > >       
> > I thought FreeBSD had domU support at this point.  If I'm right,
> > wouldn't that help I/O performance a lot?
> >     
>
> it would, yes. if there is a FreeBSD PV kernel it would be the
> best option
>
>   

It does have domU support, altough with some problems - 
http://wiki.freebsd.org/FreeBSD/Xen

The servers I have in mind are fairly busy webservers, quad core CPUs, 
so much for low I/O.

In your experience, is the slowdown due to HVM unnaceptable? Out of 
curiosity, could the ne2000 emulated device saturate even a 100mbit link 
(I'm running on gigabit) ?

Too many questions and not enough hardware here.. :-)