A synthetic workload model for a distributed system file server

Abstract

The accuracy of the results of any performance study depends largely on the quality of the workload model driving it. Not surprisingly then, workload modelling is an area of great interest to those involved in the study of computer system performance. While a significant amount of research has focussed on the modelling of workloads in a centralized computer system, little has been done in the context of distributed systems. The goal of this research was to model the workload of a distributed system file server in a UNIX/NFS environment. The resulting model is distribution-driven and generates workload components in real time. It runs externally to the system it drives, thus eliminating any interference at the server. The model was validated for different workload intensities to ensure that it provides the flexibility to vary the workload intensity without loss of accuracy.