A Dynamic Window-Constrained Scheduling Algorithm for Multiprocessor Real-Time Systems

Abstract

Advances in computing applications in recent years have prompted the demand for more flexible scheduling models and multiprocessor scheduling algorithm. The DWCS (dynamic window-constrained scheduling) is a flexible scheduling algorithm. In the scheduling algorithms on multiprocessor real time systems, the heuristic algorithm is an important algorithm and a known heuristic algorithm is myopic algorithm [1]. The performance of the myopic algorithm is greatly based on heuristic functions. In this paper, we present an improved heuristic algorithm, which has a new heuristic function for window-constrained real-time tasks. The improved algorithm considers not only the deadlines and the resource requirements of a task, but also the processing time of the task. The most important metric for real-time scheduling algorithms is scheduling success ratio. To evaluate the effectiveness of the improved algorithm, we have done extensive simulation studies. The simulation results show that the scheduling success ratio of the improved heuristic algorithm is superior to that of myopic algorithm.