Hyper-V architecture Hyper-V is the first hypervisor of Microsoft that gets installed directly on hardware. In terms of architecture is Hyper-V not an application that gets installed on Windows Server 2008. Hyper-V expresses itself directly into the hardware and supports isolation in the form of partitions. A partition is a logical unit in which an operating system is installed. A hypervisor instance needs at least one parent partition in which Windows Server 2008 operates. The virtualisation stack operates in the parent partition and had direct access to the hardware. The parent partition creates the child partitions in which the virtual Machines get installed.
Child partitions don’t have direct access to the hardware but have so called ‘virtual devices’. Every request for a virtual device gets processed by the VMBus. Virtual devices can make use of Enlightened I/O. This is a part of Windows Server Virtualization and is supported by multiple guest operating systems such as: Windows 2008, Windows Vista, Red Hat Enterprise Linux and SUSE Linux. Because of them using Enlightened I/O these operating systems have inside a VM a better performance.