Analyzing queueing networks with simultaneous resource possession

This paper describes the "method of surrogates," an approximate solution technique for queueing network models that include the simultaneous or overlapped possession of resources. Simultaneous resource possession arises in many computer system contexts and can have a significant effect on system performance. It poses difficulties in analytic modeling because it violates certain assumptions that are essential to separable or product form queueing networks. Efficient exact solution techniques are thus inapplicable and approximate solution techniques must be used.