Pythia: A Performance Analyzer of Hierarchical Mass Storage Systems

The constant growth on the demands imposed on hierarchical mass storage systems creates a need for frequent reconfiguration and upgrading to ensure that the response time and other performance metrics are withing the desired service levels. This paper describes the design and operation of Pythia; a tools that assists system managers and integrators in making cost-effective procurement decisions. Pythia automatically builds and solves an analytic model of a mass storage system based on a graphical description of the architecture of the system and on a description of the workload imposed on the system. In addition to solving the baseline model, the tool can perform a number of experiments. The experiments are throughput and response time versus workload intensity and throughput and response time versus hit ratio. Keywords--- Performance modelling, mass storage systems, queueing networks, performance tools. I. Introduction Hierarchical mass storage systems are becoming more complex each..