Energy management for hypervisor-based virtual machines

Current approaches to power management are based on operating systems with full knowledge of and full control over the underlying hardware; the distributed nature of multi-layered virtual machine environments renders such approaches insufficient. In this paper, we present a novel framework for en-ergy management in modular, multi-layered oper-ating system structures. The framework provides a unified model to partition and distribute energy, and mechanisms for energy-aware resource account-ing and allocation. As a key property, the frame-work explicitly takes the recursive energy consump-tion into account, which is spent, e.g., in the virtu-alization layer or subsequent driver components. Our prototypical implementation targets hyper-visor-based virtual machine systems and comprises two components: a host-level subsystem, which con-trols machine-wide energy constraints and enforces them among all guest OSes and service components, and, complementary, an energy-aware guest oper-ating system, capable of fine-grained application-specific energy management. Guest level energy management thereby relies on effective virtualiza-tion of physical energy effects provided by the vir-tual machine monitor. Experiments with CPU and disk devices and an external data acquisition system demonstrate that our framework accurately controls and stipulates the power consumption of individual hardware devices, both for energy-aware and energy-unaware guest operating systems.