Energy minimization for embedded systems with discrete voltage levels

Energy minimization for multi-core embedded systems is one of the most important issues, as well as performance. When the transition time of supply voltage is a constant, appropriate execution order of tasks can decrease the number of voltage transition and save the energy overhead of voltage transition. This paper proposes a scheduling algorithm for multi-core embedded systems running periodic dependent tasks with hard time constraints, considering transition overhead as well as communication overhead. Based on the retimed task graphs produced by the RDAG algorithm, we execute tasks mapping and reorder the execution order of tasks by descending voltage levels. We conduct experiments on a set of random task sets. The results show that the proposed algorithm achieves substantial energy savings compared with previous work.