Parallel Job Scheduling: Issues and Approaches

Parallel job scheduling is beginning to gain recognition as an important topic that is distinct from the scheduling of tasks within a parallel job by the programmer or runtime system. The main issue is how to share the resources of the parallel machine among a number of competing jobs, giving each the required level of service. This level of scheduling is done by the operating system. The four most commonly used or advocated techniques are to use a global queue, use variable partitioning, use dynamic partitioning, and use gang scheduling. These techniques are surveyed, and the beneets and shortcomings of each are identiied. Then additional requirements that are not addressed by current systems are outlined, followed by considerations for evaluating various scheduling schemes.