[PVE-User] Question about memory management

[CDR]

I am using KVM and I found a fatal, unsurmountable issue with Windows
Virtual machines. It turns out that if I assign 5 GB to a Windows 2003
or Windows 2008 Virtual machine, the whole amount of memory is taken
from the host, without considering that only about 350 Mb of the total
is actually being used. This is insane. I opened a support ticket with
Red Hat, and they claim that Windows zeros out all memory and that by
doing so, it appears to be in use. So they laughed at me. But, hey, I
replied, Vmware has that feature working fine since years ago. In
fact, I checked on my own Vsphere 4.1 servers and the windows machines
show a very large difference between the memory assigned, nominally,
to the virtual machine and the actual memory used by it in the host.
So, if they solved t, why Red Hat claims that there is no solution?
Any idea?
Federico