端到端实时任务调度模型可用于描述许多分布式实时系统.提出一种基于EDF调度策略的端到端实时任务调度模型,给出了端到端实时系统的可调度性判定条件,并提出其可调度性分析算法,该可调度性判定条件及可调度性分析算法适用于采用非连续工作型同步协议和连续工作型同步协议控制下的端到端实时系统.与固定优先级的端到端实时任务调度模型及其算法相比,基于EDF调度策略的端到端实时任务调度模型和算法更加简单和易于实现,仿真结果也表明具有较高的性能.
An end-to-end real-time scheduling model can be used to describe many distributed real-time systems. In this paper, an EDF-based end-to-end real-time scheduling model is proposed. According to the time demand analysis technique, a schedulability condition for the end-to-end real-time system is deduced. Then, a schedulability analysis algorithm is developed. The schedulability condition and schedulablity analysis algorithm are suitable not only for end-to-end real-time systems controlled by non-greedy synchronization protocols, but also for those controlled by greedy synchronization protocol. Compared with fix-priority-based end-to-end real-time scheduling model and its algorithms, the model and algorithm proposed in this paper are simpler and easier to implement. Simulation results reveal that higher performance can be achieved too.