TimeAdapt

Abstract

Real-time embedded systems such as those in the avionics, automotive and robotics domains run in highly complex and unstable environments. These systems need to be adaptive in order to maintain required levels of quality of service in dynamic environments. Dynamic software reconfiguration mechanisms support adaptations in such environments without the need to restart the system. However, the highly dynamic nature of real-time embedded systems in unstable environments raises new challenges for reconfiguration, such as the need for timely execution. Current programming frameworks and middleware for real-time embedded systems either do not address dynamic reconfiguration at all, or omit timeliness from consideration.In this paper we present TimeAdapt that supports the execution of reconfigurations on component-based real-time applications in a timely manner. The system design follows a three-tiered approach: For each reconfiguration, a probability is estimated as to whether the given time bound can be met. If the probability is high enough (as specified by the application), the reconfiguration is scheduled for execution as a real-time task. TimeAdapt also includes a reconfiguration specification language and a component model that supports dynamic reconfigurations on its elements.