This simulation tool allows the user to explore different computer architectures with hardware support at any or all of five levels of parallelism, from intrainstruction (pipeline) through distributed n -tier client/server systems. The tool supports the simulation of various user-configurable architectures and interconnection networks, running a user-configurable and variable workload. This allows the student and the instructor to observe how performance changes through the five levels of parallelism with changes in either the architecture or workload. The successful use of the simulation tool in a variety of undergraduate courses at the author's institution is presented, along with examples, and a set of experiments. The simulator is a Java applet, which can be used from a Web browser, allowing anyone with an Internet connection access to the tool, without concern about student licensing requirements. The simulator is hosted at the author's institution with funding provided by a recent grant. Its design as an applet also allows improvements and enhancements to the software to be implemented and instantly made available to all users of the product.

A model of system performance for parallel processing on clustered multiprocessors is developed which unifies multiprogramming with speedup and scaled-speedup. The model is used to explore processor to process allocation alternatives for executing a workload consisting of multiple processes. Heuristics are developed that relate cluster size to parallel fraction of a program and to process scaling factors. The basic analytical model is made more sophisticated by incorporating considerations that affect the realizable speedup, including explicit process scaling, Degree of Parallelism (DOP) as a discrete function, and communication overhead. New developments incorporate nonuniform workload, interconnection network probability of acceptance of requests, nonuniform memory access, and multithreaded processes.