Energy minimization for checkpointing-based approach to guaranteeing real-time systems reliability

In this paper, we study the energy minimization problem for a frame-based real time system with guaranteed reliability using the checkpointing technique. We formally prove that executing a real time task set with a uniform frequency, or neighboring frequencies if the desired frequency is not available, not only optimizes its energy consumption but also achieves maximal reliability. Based on the theoretic conclusion, we further develop a Dynamic Voltage Frequency Scaling (DVFS) and checkpoint allocation strategy for a task set to guarantee both reliability and deadline constraints but with minimal energy consumption. The proposed strategy has very small frequency switching overhead as no more than one frequency change is needed for the entire task set execution and thus is particularly effective for processors with large frequency switching overhead. We further empirically compare our approach with recent work published in the literature. The experimental results show that the proposed approach can reduce as much as 15% energy consumption.