COMPUTER SYSTEMS PERFORMANCE EVALUATION BY SIMULATION

Abstract

Performance evaluation plays a very important role in the study of computer systems. The various techniques available for evaluating performance of a computer systems are by - analytical models, direct measurement and simulation of the system. It is usually difficult to adopt analytic method for evaluating performance of complex systems. Direct measurement technique is possible only when the system is operational. However, simulation technique overcomes both of these difficulties and can be used advantageously for evaluating performance during design and development phases. This thesis addresses the problems of design and development of simulation program for performance evaluation of three simple models of computer system. The work demonstrates the effectiveness and simplicity of simulation technique. Simulation models are constructed for performance analysis of a simple batch system, a central server model and a multiple- bus multiprocessor system with shared resources. Performance modelling is a pre -requisite of developing a simulation model. Benefit of performance modelling is the insight into the structure and behaviour of the'system that is obtained in the course of developing a model. Performance measures of concern, for the first two problems, are utilization, throughput, mean queue length, response time etc. For a multiple - bus multiprocessor system, processor efficiency and bandwidth of the system are the important performance measures