Modelling Parallel Service Systems in GPSS

Abstract

This article treats parallel service system modelling in the GPSS simulation language. The transactions entering such systems select between numerous different servers and we can mostly detect two rules in the selecting of the appropriate server. The first rule always gives the first few (regarding its position in the system) entities (either servers or queues) precedence over the others, while the second rule always treats all the equal entities evenly and selects among them quite randomly. Since GPSS normally operates by the first rule, we frequently come up against difficulties when modelling systems that serve by another rule. The present article offers a methodology how to solve this problem within GPSS.