The Power Broker: Intelligent Power Management for Mobile Computers

Technology has improved processor speed and memory densities at exponential rates. Rapid advances in portable computing have resulted in laptop computers with performance and features comparable to their desktop counterparts. Battery technology has failed to keep pace, decreasing the usefulness of mobile computers and portable wireless devices. We provide a detailed analysis of power consumption typically encountered in a networked laptop computer and the power management methods currently used. We then show how interaction between independent power consumers results in inefficient use of energy resources and propose the Power Broker as a means for orchestrating energy use with the goal of extending battery life. The Power Broker's resource management algorithms exploit an abundant resource (CPU power) to conserve a scarce one (battery energy).