XEN newcomer!

[Roy Marples <roy%marples.name@localhost>]

Hi List

I'm getting a piece of kit for Christmas, namely a low powered Intel 
Celeron J1900 to replace my existing server (has an Intel Atom D510 for 
comparsion)
http://www.gigabyte.com/products/product-page.aspx?pid=5118#ov

The chipset has VT-x which is nice for the price, but lacks VT-d.
Is this a concern for running NetBSD/Xen? I found this post on FreeBSD:
https://lists.freebsd.org/pipermail/freebsd-xen/2015-October/002558.html
Which indicates FreeBSD/Dom0 requires VT-d. I cannot find any 
documentation on whether NetBSD/Dom0 requires VT-d or not. Certainly the 
main Xen documentation suggests that it's optional. Infact, the 
NetBSD/Xen howto only makes mention of VT, not VT-x or VT-d.

Here is the only clue from:
http://wiki.netbsd.org/ports/xen/howto/
Some versions of Xen support "PCI passthrough", which means that 
specific PCI devices can be made available to a specific domU instead of 
the dom0. This can be useful to let a domU run X11, or access some 
network interface or other peripheral.

Now, I don't need PCI passthrough at all as the box will just be running 
a clone of my existing server as a DomU for the most part, but spinning 
up other VM's just for development purposes as requested. I'm also 
hoping that even without VT-d the performance will still be faster than 
my old server.

Lastly, the howto could be improved with other NetBSD specific pieces I 
found here:
https://gmplib.org/~tege/xen.html
Interestingly, that notes that guide talks about xentools46 whereas our 
how to talks about testing xentools45. So maybe our guide could do with 
some updating here.
I intend to install the latest available for NetBSD-7 and scale back if 
it fails.

Roy