多处理器实时系统中的非精确轮转式调度算法  

An Imprecise Computation-Rotational Scheduling Algorithm in Multiprocessor Real-Time System

作　　者：周悦[1] 刘晓林[1] 王惠宁 

机构地区：[1]沈阳建筑大学信息与控制工程学院,辽宁沈阳110168 [2]爱斯阿尔房产开发有限公司,辽宁沈阳110015

出　　处：《沈阳建筑大学学报（自然科学版）》2008年第5期920-923,共4页Journal of Shenyang Jianzhu University：Natural Science

基　　金：辽宁省博士启动基金(20041002);辽宁省教育厅基金(2004F044)

摘　　要：目的研究基于多处理器实时系统中具有截止期和容错需求任务的非精确轮转式调度算法,使强实时系统在发生故障的情况下,任务也能在其截止期内完成,不至产生灾难性后果.方法将非精确计算模型引入到轮转式调度算法中.结果仿真实例表明,非精确轮转式调度算法具有更低的任务拒绝率,同时能更为有效地利用系统资源.结论该算法扩展了轮转式调度算法的允许调度定理,使得主/副版本任务在执行时间上可以重叠,提高了任务的可调度性,使整个系统负载均衡,并减少了系统搜索时间.In this paper, an imprecise computation- rotational scheduling algorithm for the tasks in multi-processor real - time system which have timing and fault - tolerant constraints is researched, by which, in the presence of hardware component failures in hard real - time system, tasks still can be executed in their deadline, and the system cannot have disastrous results. Imprecise computation model was introduced to rotational scheduling algorithm. The analysis of simulative experiment illustrates that the imprecise computation - rotational scheduling algorithm has lower ratio of task refuse, and gets better utilization of system resources. The schedule theorem of rotational scheduling algorithm is improved, and the primary and backup execution time may overlap each other. The new algorithm enhances the schedulbility of tasks; the load of system is balanceable, and the search time of the system is reduced.

关 键 词：实时 容错 非精确 轮转式调度 

分 类 号：TP13[自动化与计算机技术—控制理论与控制工程]