Summary form only given, as follows. Performance evaluation of multiple-bus mutiprocessor systems is usually carried out under the assumption of uniform memory reference model. Hot spots arising in multiprocessor systems due to the use of shared variables, synchronization primitives etc., give rise to nonuniform memory reference patterns. The objective of this paper is to study the performance of multiple-bus multiprocessor systems in the presence of hot spots. Analytic expressions for the average memory bandwidth and probability of acceptance of prioritized processors have been derived. The results are validated by simulation results.