Dynamic counters and the efficient and effective online power management of embedded real-time systems

Energy consumption has become an important issue for modern embedded systems. This is because, one does not only like to deploy high-performance systems and provide guaranteed services, but also request system deployments to last as long as possible. With online dynamic power management (DPM), one adaptively changes the system's power mode, i. e., schedules when to turn on and off on-the-fly, to achieve energy savings. This paper introduces dynamic counters and discusses their usage in the context of (online) DPM in a setting where systems have to fulfill hard real-time requirements. The proposed scheme enables one to conservatively bound the future workload and thereby to safely schedule on- and off-periods of devices. Simulation results indicate that the proposed technique is more efficient and more effective with respect to energy savings, compared to previous work.