Load Dependent Single Chain Models of Multichain Closed Queueing Networks

Often a multichain product form queueing network is used to model a complex computer system. In many cases, the multichain demands are unavailable or are difficult to obtain. In contrast, load dependent demands are often directly measurable. This paper investigates the use of a load dependent single chain model as an approximate model of an actual multichain system. In restricted cases, it is shown that the load dependent single chain counterpart model of an actual multichain system is exact. In random unrestricted cases, it is shown that the load dependent model is a good approximation to the actual multichain system. It is demonstrated that the load dependent model can also be used effectively for predictive purposes. Index Terms: load dependent models, multichain closed product form queueing networks, performance prediction, parameter measurements, approximation errors, workload characterization This work was partially supported by sub-contract 19X-SL131V from the Oak Ridge Nation..