This is done to eliminate the dependency on a single sequence of pseudo-random numbers and to establish confidence intervals on the performance measures. Distribute one replication to each processor, and designate one processor to collect the statistics emanating from the computation. This is exactly what we did for a recent study of a small production system under various conditions. To do this efficiently, we constructed a distributed simulator architecture that ran on about one dozen Sun Sparcstations, mainly SparcStation 10s. The computers used were the MTL machines, the machines at the Operations Research Center, and a single SparcStation 10 at the Norwegian Defence Research Establishment.
Figure shows the general topology.
After the actual study was completed, a Pentium 100MHz PC running Linux was added to the architecture. This demonstrates that the architecture is not Sun-specific. The discrete event simulation is a relatively small and efficient C program based on the CAFE scheduling and simulation testbed. This version was rewritten for efficiency in time and memory, so a lot of the more impressive features of the testbed were left out. It did, on the other hand, include more statistics collection and reporting than the testbed.