Dynamic Voltage and Frequency Scaling for Optimal Real-Time Scheduling on Multiprocessors

Not only system performance but also energy efficiency is critically important for embedded systems. Optimal real-time scheduling is effective to not only schedulability improvement but also energy efficiency for the systems. In this paper, Real-Time Dynamic Voltage and Frequency Scaling (RT-DVFS) techniques based on the theoretically optimal Real-Time Static Voltage and Frequency Scaling (RT-SVFS) techniques proposed in the previous work are presented for multiprocessor systems. Simulation results show that RT-DVFS covers up the disadvantages of RT-SVFS in the sense that RT-DVFS are not practically affected by the difference among systems, whereas the energy consumption of RT-SVFS highly depends on the selectable processor frequency especially in high system utilization.