Worst-case utilization bound for EDF scheduling on real-time multiprocessor systems

In this paper we present the utilization bound for Earliest Deadline First (EDF) scheduling on homogeneous multiprocessor systems with partitioning strategies. Assuming that tasks are pre-emptively scheduled on each processor according to the EDF algorithm, and allocated according to the First Fit (FF) heuristic, we prove that the worst-case achievable utilization is 0:5(n + 1), where n is the number of processors. This bound is valid for arbitrary utilization factors. Moreover, if all the tasks have utilization factors under a value , the previous bound is raised, and the new utilization bound considering is calculated. In addition, we prove that no pair of uniprocessor scheduling algorithm-allocation algorithm can provide a higher worst-case achievable utilization than that of EDFFF. Finally, simulation provides the average-case achievable utilization for EDF-FF.