Optimal procrastinating voltage scheduling for hard real-time systems

This paper presents an optimal procrastinating voltage scheduling (OP-DVS) for hard real-time systems using stochastic workload information. Algorithms are presented for both single-task and multi-task workloads. Offline calculations provide real-time guarantees for worst-case execution, and online scheduling reclaims slack time and schedules tasks accordingly. The OP-DVS algorithm is provably optimal in terms of energy minimization with no deadline misses. Simulation results show up to 30% energy savings for single-task workloads and 74% for multi-task workloads compared to using a constant worst-case execution voltage. The complexity of the algorithm for multi-task workloads is linear to the number of tasks involved.