When Hyper-V runs as a role on Windows Server 2008 et Windows Server 2008 R2 c'est encore a hypervisor.
C'est a type 1 (bare metal) hypervisor in les deux cases.
The trick here is that quand you install Hyper-V as a role on Windows Server 2008 R2 you see le Windows Server like a host OS et it is not. The setup converts le original OS in something like a VM et puts le hypervisor below. Ceci est what is called le root ou parent partition of Hyper-V. C'est why you experience le même sped in what you see as le "real machine" et le virtual machines.
Vous pouvez find le Hyper-V Architecture at MSDN.
