为了提高硬实时系统的容错能力，同时减少任务间的抢占次数，基于软件容错模型提出了抢占阈值容错调度算法(FT-FPPT). -Software-based fault-tolerant model in order to improve the fault tolerance of the hard real-time systems, while reducing the number of task preemption, preemption threshold tolerant schedu