A queuing model for service availability of systems with rejuvenation

In this paper we present a queuing model to investigate the effect of time-based system rejuvenation on service availability. The model is formulated as a stochastic colored Petri net, which allows us to use realistic distributions such as the lognormal distribution. We define a metric for service availability and derive how it can be estimated from the model. Experiments show that the optimal rejuvenation interval as well as the achievable service availability improvement depend significantly on system utilization.