Abstract:

In order to improve the efficiency of fault tolerant scheduling of hybrid real time tasks in circumstance of space application, a hybrid fault tolerant scheduling algorithm for multiprocessor in space environment is proposed. In this algorithm, a grouping based Best Fit assignment strategy in the periodic task scheduling is used to obtain more compact scheduling result by use of a little increasing computation time, so that the number of processors and the task execution time required by the algorithm are saved. In addition, a time slice based approach is used to finish the dynamic scheduling of aperiodic tasks, thus improving the efficiency of fault tolerant scheduling of hybrid real time tasks and making the algorithm more suitable for the task processing in complicated space environment. It is shown from the simulation that this algorithm has important effect on improving the performance of fault tolerant scheduling of hybrid real time tasks.

Key words: Grouping, Fault tolerant, Hybrid task, Scheduling algorithm, Space environment