Hybrid Simulation Models of Computer Systems This paper describes the structure and operation of a hybrid simulation model in which both discrete-event simulation and analytic techniques are combined to produce efficient yet accurate system models. In an example based on a simple hypothetical computer system, discrete-event simulation is used to model the arrival and activation of jobs, and a central-server queueing network models the use of system processors. The accuracy and efficiency of the hybrid technique are demonstrated by comparing the result and computational costs of the hybrid model of the example with those of an equivalent simulation-only model. CACM September, 1978 Schwetman, H. Performance evaluation, simulation, queueing network models, central server model 4.32 4.35 8.1 CA780902 DH February 5, 1979 3:32 PM 2712 4 3070 2741 4 3070 3016 4 3070 3059 4 3070 3070 4 3070 3070 4 3070 3070 4 3070 3070 4 3070 3153 4 3070 1805 5 3070 2454 5 3070 2741 5 3070 2988 5 3070 3070 5 3070 3070 5 3070 3070 5 3070