Operating-system directed power reduction

This paper presents a new approach for power reduction by taking a global, software-centric view. It analyzes the sources of power consumption: tasks that require services from hardware components. When a component is not used by any task, it can enter a sleeping state to save power. Operating systems have detailed information about tasks; therefore, OS is the best place for power reduction. Our technique is effective in identifying hardware idleness and shutting down unused components. We implement this technique in Linux and show that it can save more than 50% power compared to traditional hardware-centric shutdown techniques.