Energy efficient SEU-tolerance in DVS-enabled real-time systems through information redundancy

Concerns about the reliability of real-time embedded systems that employ dynamic voltage scaling has recently been highlighted [R. Melhem, D. Mosse, E. Elnozahy (2004), Y. Zhang, K. Chakrabarty (2004) and D. Zhu, R. Melhem, D. Mosse (2004)], focusing on transient-fault-tolerance techniques based on time-redundancy. In this paper we analyze the usage of information redundancy in DVS-enabled systems with the aim of improving both the system tolerance to transient faults as well as the energy consumption. We demonstrate through a case study that it is possible to achieve both higher fault-tolerance and less energy using a combination of information and time redundancy when compared with using time redundancy alone. This even holds despite the impact of the information redundancy hardware overhead and its associated switching activities.