【摘要】 在混合实时系统中,调度器必须既保证所有硬实时任务严格按照其时间约束在截止期内完成,又要尽可能地提高软实时任务和非实时任务的服务质量.提出了一种严格按比例派发服务器算法(RPDS),并以此为基础构建了一种层次式调度框架.RPDS将处理器时间流分成连续的小段,并在每一小段中强制为非硬实时任务分配一个时间片.实验结果表明,RPDS可以合理地为各种类型应用分配处理器时间,并且降低了实时任务的截止期错失率.更多还原

【Abstract】 In hybrid real-time systems, schedulers must guarantee that all of hard real-time jobs are finished by their deadlines and the QoS of soft real-time tasks and non real-time tasks are improved as greatly as possible. This paper presents RPDS (rigorously proportional dispatching server) algorithm, and constructs a hierarchical scheduling framework based on that. RPDS partitions CPU time flow into continuous segments, and in each segment RPDS will forcibly assign one time slice to non-hard real-time tasks. Experimental results show that RPDS can allocate processor time to various application classes reasonably and reduce the deadline miss ratio of real-time tasks effectively.更多还原