Service Improvements in Real-Time Uniprocessor Scheduling With Single Errors

Abstract

Mixed-criticality scheduling in modern deeply embedded mission and safety-critical systems needs to consider delivered service, that is, the runtime in low criticality mode. If the change into a higher criticality mode is triggered by the first overrunning job, the service is severely reduced. With earliest deadline first with virtual deadlines for single errors (EDF-VD-SE) we show how to reserve additional time to tolerate a single overrunning job by formulating and solving an optimization problem, and that EDF-VD-SE is feasible without assumptions about error probabilities for safety guarantees. We conduct extensive simulation experiments to report on average doubled service figures, and show how EDF-VD-SE results in a nearly constant acceptance rate of random task systems.

Keywords

• Real-time systems
• scheduling algorithms
• system recovery