云计算中基于任务分层和时间约束的关联任务调度算法

Related task scheduling algorithm based on task hierarchy and time constraint in cloud computing

针对云计算中对关联任务进行调度时出现任务执行延迟的问题,提出了一种基于任务分层和时间约束的关联任务调度(RTS-THTC)算法。该算法采用构建有向无环图(DAG)的方式表示关联任务的执行次序,通过使用对DAG进行分层的方法提高任务的并行性,计算每一层任务的完成时间约束,将每一层中的任务同时调度至具有最小完成时间的资源上。与基于异构环境的最小完成时间(HEFT)算法的对比实验结果表明,RTS-THTC算法在完成时间上比HEFT算法短,并且能够有效地减缓关联任务出现延迟的情况。

Concerning the delay of related task scheduling in cloud computing, a Related Task Scheduling algorithm based on Task Hierarchy and Time Constraint（ RTS-THTC） was proposed. The related tasks and task execution order were represented by Directed Acyclic Graph（ DAG）, and the task execution concurrency was improved by using the proposed hierarchical task model. Through the calculation of the total time constraint in each task layer, the tasks were dispatched to the resource with the minimum execution time. The experimental results demonstrate that the proposed RTS-THTC algorithm can achieve better performance than Heterogeneous Earliest-Finish-Time（ HEFT） algorithm in the terms of the total execution time and task delay.