在多处理器实时系统中,由于调度的不规则性,系统的可预测性判定问题尤为重要。针对多处理器系统中实时任务调度的可预测性问题,给出了不可预测的实时任务集反例,证明了一种可预测的实时任务集合。对于多处理器实时系统中常用的最早截止期零松弛调度算(earliest deadline zerolaxity,EDZL)的可预测性,利用EDZL算法的基本性质,用一种简捷的方法证明了EDZL算法是可预测的。通过仿真系统验证了证明的正确性,该方法可用于多处理器及分布式实时系统的设计和验证。
In the multiprocessor real-time systems, because of scheduling irregularities, the predictability of the real-time system isparticularly important. According to the predictability ofreal-time scheduling on multi-processor system, acounter-examplethatarealtime task set can not be predicted is given, and one kind of predictable real-time task set is proved. For predictability of EDZL (earliest deadline zero laxity) algorithm commonly used in multi-processor real-time systems, a simple way is used to prove that EDZL algorithm is predictable based on properties of the algorithm. The proof is verified by simulation. A way for multi-processor real-time systems design and verification is given.