Analyzing stochastic fixed-priority real-time systems

Abstract

Traditionally, real-time systems require that the deadlines of all jobs be met. For many applications, however, this is an overly strin- gent requirement. An occasional missed deadline may cause decreased performance but is nevertheless acceptable. We present an analysis tech- nique by which a lower bound on the percentage of deadlines that a peri- odic task meets is determined and compare the lower bound with simula- tion results for an example system. We have implemented the technique in the PERTS real-time system prototyping environment [6, 7].