Over the last decade, much research in the area of scheduling has concentrated on single cluster systems. Less attention has been paid to multicluster systems, although they are gaining more and more importance in practice. We propose a model for scheduling rigid jobs consisting of multiple components in multicluster systems by pure space sharing, based on the Distributed ASCI Supercomputer. Using simulations, we asses the in.uence of the structure and sizes of the jobs on the system’s performance, measured in terms of the average response time and the maximum utilization. We consider three types of requests, total requests, unordered requests and ordered requests, and compare their effect on the system’s performance for two scheduling poli...