Fault Recovery Based on Checkpointing for Hard Real-Time Embedded Systems

Safety-critical embedded systems often operate in harsh environmental conditions that necessitate fault-tolerant computing techniques. Many safety-critical systems also execute realtime applications. The correctness of these systems depends not only on the logical result of computation, but also on the time at which the results are produced. The missing of task deadlines can therefore be viewed as a temporal fault. In this paper, we examine fault recovery based on checkpointing for real-time systems. We present schedulability tests for checkpointing in real-time systems. These feasibility-of-scheduling tests provide the criteria under which checkpointing can provide fault tolerance and real-time guarantees for hard real-time embedded systems under two different fault arrival models.