Periodic Task Cluster Scheduling in Distributed Systems

This chapter addresses issues of task clustering — the coalition of several tasks into single coarser grain tasks called task clusters — and task cluster scheduling on distributed processors. It considers a special scheduling method referred to as periodic task cluster scheduling. With this method, processor queues are rearranged only at the end of predefined intervals called epochs. The objective is to find an epoch that minimizes the number of queue rearrangements, and that also results in good overall performance, and in fairness in individual job service. Simulation models are used to compare the performance of this method with other task cluster scheduling policies. Simulated results indicate that periodic task cluster scheduling is a good policy to use.