Expressing performance requirements using regular expressions to specify stochastic probes over process algebra models

This paper describes how soft performance bounds can be expressed for software systems using stochastic probes over stochastic process algebra models. These stochastic probes are specified using a regular expression syntax that describes the behaviour that must be observed in a model before a performance measurement can be started or stopped. We demonstrate the use of stochastic probes on a 661, 960 state parallel, redundant web server model to verify its passage-time performance characteristics.