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.
Ashok Argent-Katwala, Jeremy T. Bradley, Nicholas