Rejuvenation Modeling in Safety Critical Real Time Systems using Stochastic Petri Nets

The main idea behind the increase in use of real time systems is that their performance is measured in terms of clock time and not on the basis of logical time which imposes timing constraints on the performance evaluation of such systems. It is a fact that any software with aging becomes prone to failure. Mostly the complex systems are safety critical systems whose reliability is the most important performance measure. Such systems need to be safeguarded from the effects of aging. This could be done either by debugging the errors or through preventive maintenance like rejuvenation. Although the downtime cost due to rejuvenation may make it appear expensive, but it enhances the reliability of the software. This paper studies the effect of rejuvenation on a real time system from the estimated values of performance measures based on SPNP tool.