基于固定优先级航天器任务分层调度研究

Spacecraft Task Hierarchical Scheduling Analysis Within Fixed Priorities

在航天器自主控制结构中,采用分层结构构建系统,实现不同分组的软件互不影响执行。针对固定优先级调度模型,通过对分区可调度性和分区设计问题进行研究,仔细考察了任务最大响应时间迭代计算过程,提出了一种更为精确的求解算法;在固定优先级任务利用率上限的基础上,给出了分区任务可设计的判定条件;通过利用价值函数,给出了分区参数解析模型,在此基础上,提出了一种局部最优的设计方法来实现整个处理器的分区设计,通过具体实例对所提出的分区分析和设计方法进行了验证。

In the autonomous control architecture for spacecraft, layered structure style is adopted. It manages all categorical applications through partition management to avoid interaction among them. This paper focuses on the partition schedulablity analysis and the partition design for fixed priorities scheduling model. It introduces a more exact partition task worst-case response time algorithm through observing the actually iterative operator, and addresses a partition designable condition based on the upper limit of the task utilization factor within the fixed priorities. By using the cost function, it also proposes the partition key parameters resolution model and a local optimal algorithm to implement the whole processor partition design. At last, it introduces a practical example to illustrate the validity of the analysis and design methodology.