Vitri - A Generic Framework for Engineering Decision Support Systems on Heterogeneous Computer Networks

Abstract

Vitri is an object-oriented framework implemented in Java for high-performance distributed computing. Using Vitri, applications can engage in cooperativeproblem solving by dividing their tasks among heterogeneous clusters of workstations and PCs. Vitri's features include basic support fordistributed computing and communication, as well as visual tools for evaluating run-time performance, and modules for heuristic optimization. It balances loads dynamically using a client-side task pool, allows theaddition or removal of servers during a run, and provides fault tolerance transparently for servers and networks. Among its more powerful featuresare modules for heuristic optimization and decision support tools such asmodeling to generate alternatives (MGA). Vitri also provides an asynchronous global-parallel genetic algorithm that is particularly suited for coarse-grained tasks executing on processors with large variations in processor speeds. By using dataflow techniques, in which computations areexplicitly based on the availability and forwarding of data, the usual end-of-generation synchronization points are removed from the algorithm. The tools in Vitri are applied to a number of different applicationsfrom the civil engineering domain. The results indicate the adaptability of Vitri to various problems and its utility as a tool for managing engineering decision support systems.