Energy efficient DVS schedule for fixed-priority real-time systems

Abstract

Energy consumption has become an increasingly important consideration in designing many real-time embedded systems. Variable voltage processors, if used properly, can dramatically reduce such system energy consumption. In this paper, we present a technique to determine voltage settings for a variable voltage processor that utilizes a fixed-priority assignment to schedule jobs. By exploiting more efficiently the processor slack time, our approach can be more effective in reducing the execution speed for real-time tasks when necessary. Our approach also produces the minimum constant voltage needed to feasibly schedule the entire job set. With both randomly generated and practical examples, our heuristic approach can achieve the dynamic energy reduction very close to the theoretically optimal one (within 2%) with much less computation cost.