Preemptive Weighted Completion Time Scheduling of ParallelJobs ? Uwe

In this paper we present a new algorithm for the oo-line scheduling of parallel and independent jobs on a parallel processor system. To this end we introduce a machine model which is based on existing multiprocessors and accounts for the penalty of preemption. After examining the relation between the makespan and the total weighted completion time costs for the scheduling of parallel jobs it is shown that the new algorithm achieves a small approximation factor for both total weighted completion time and makespan scheduling. To ne tune the algorithm a fairly simple numerical optimization problem is derived. This way diierent preemption penalties can be considered when determining the approximation factor. Finally, we compare the costs of the generated preemptive schedules with those of non-preemptive schedules for the same problem.