Energy Accounting for Virtual Machines

This thesis presents a two-level approach to energy accounting in virtual machine environments. Instead of accounting the energy consumption of the hardware directly to the applications, as done by previous approaches, we account it to virtual machines. Each guest operating system can then obtain the energy consumption of the virtual machine and split it between its applications. Thus, energy management can leverage information intrinsic to the respective level. Furthermore, by dividing energy accounting between host-level and guest-level, we can reuse existing energy management solutions within the virtual machines. For this purpose, we introduce an energy-aware virtual machine interface, which enables the guest operating systems to estimate the energy consumption of virtual devices. To evaluate our approach, we implemented a prototype for an existing virtual machine environment. Experiments show that the performance overhead caused by energy accounting in host-level and guest-level is less than 3.2 percent.