提出了一种基于时间事件模型的实时系统时序分析方法。该方法以仿真为基础对目标系统进行分析,不仅可以描述实时系统的周期和非周期任务,各种同步事件以及与时间有关的行为特征,而且还能够刻画实时系统中多个任务间的通信与同步特性;通过基于优先级的可抢占式的任务调度算法对目标模型进行仿真执行,并基于仿真结果对其进行时序分析,如任务响应时间和执行时间等,避免了形式化分析方法存在的状态空间爆炸问题。最后通过实例验证本模型与方法的有效性与实用性。
A timed event model and simulation based approach was proposed to analyze timing properties of real-time systems.The timed event model was used to specify periodic or aperiodic tasks,the timing behaviors and the inter-tasks communication and synchronization behaviors of real-time systems.The approach used a priority-based preemptive scheduling algorithm to simulate models,and then got the timing properties,such as response time,execution time,etc.,via analyzing the execution sequence generated.Different from traditional formal methods,it has no state-explosion problem.Finally,a case study was proposed to validate the model and show the practicability of the approach.