基于检查点机制的容错实时调度算法CP-PRA

CP-PRA-Fault-tolerant real time scheduling based on checkpointing scheme

时间冗余作为容错的重要手段被广泛应用于安全关键实时系统中。传统客错调度算法为失败任务的重运行(Re-execute)预留了大量的空闲时间,但是重运行的使用会降低系统的资源利用率。提出了一种基于检查点机制的容错调度算法CP-PRA,通过降低错误恢复需要的时间,可以有效地提高系统的资源利用率。给出了该算法的可调度条件,并证明了其算法的正确性。

Time redundancy has been used widely in most safety critical real-time systems to tolerate the transient faults. Most traditional fault-tolerate algorithms reserved too much spare time for failure task to re-execute with the support of scheduler. The main problem of these algorithms was the reduction of the upper bound of resource utilization. CP-PRA, a new variations of RMS based on checkpointing scheme was presented. Throught reducing the need of spare time, CP-PRA could improve the schedulability bounds for the sets of real-time tasks given by the desired level of fault tolerance for each task. Finally, the correctness of this algorithm was proved.