作者：余科军¹, 蒋毅²

作者单位：1. 四川教育学院信息技术学院, 四川成都 610041;
2. 四川理工学院计算机科学系, 四川自贡 643000

关键词：分布式实时系统; 任务分配; 任务调度; 加权轮转调度算法; 速率单调调度算法

摘要：

针对分布式实时任务中容易引起的任务分配不合理及系统负载不平衡的情况,根据分布式实时任务多机执行的特点及分布式实时系统在同一结点上有多任务执行,提出了两级分布式系统结构下实时任务的调度策略:任务分配和任务调度。实验表明,在任务分配阶段提出的算法可以更合理地平衡任务,在任务调度阶段采用的调度算法能够更好地完成任务的执行。

Design and realization of task scheduling algorithm in distributed real-time systems

YU Ke-jun¹, JIANG Yi²

1. College of Information and Technology, Sichuan College of Education, Chengdu 610041, China;
2. Dept. of Computer and Science, Sichuan University of Science and Engineering, Zigong 643000, China

Abstract: According to the unreasonableness in task allocation and load unbalancing in real time tasks distribution system, we presented the scheduling strategy that included two hierarchies: task allocation and task scheduling which was based on the characteristics of distributed real-time tasks and the character that lots of tasks are executed at the same node. The experiment showed that the algorithm that was presented at the stage of the task allocation could balance the tasks reasonably and the scheduling algorithm that was presented at the stage of the task scheduling could accomplish the tasks.

Keywords: Distributed real -time systems; Task allocation; Task scheduling; Weighted round -robin(WRR) algorithm; Rate monotonic scheduling(RMS)algorithm

2008, 34(6): 69-72  收稿日期: 2007-9-21;收到修改稿日期: 2007-12-5

基金项目: 

作者简介: 余科军(1979-),女,四川自贡市人,讲师,专业方向:网络技术。

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