Hello Matthias,

i did try the same test you did by the following setup in my environment:

Hypervisor:        Xen 2.0.5
domain0:            NetBSD 3.0_BETA (binarys from 2005-04-08)
domain1:            NetBSD 3.0_BETA (binarys from 2005-04-08)
doamin2:            NetBSD 3.0_BETA (binarys from 2005-04-08)

i've got the following output in domain0:

# dd if=/tmp/testfile of=/dev/null bs=1024k
455+1 records in
455+1 record out
477170189 bytes transferred in 8.439 secs (56543451 bytes/sec)

and the output of domain2 was:

# dd if=/tmp/testfile of=/dev/null bs=1024k
455+1 records in
455+1 record out
477170189 bytes transferred in 13.024 secs (36637760 bytes/sec)

i could'nt test the domain1 because i had a problem to get the testfile here
but it is also a partition of the same harddisk like the domain0 and 
domain2.
So i don't think that this would be much different.
Finaly, i am content with this result.

Greetings, Rainer