Reflective QoS Management and System Validation in the Real-Time Performers Architecture

The Real-Time Performers (RTP) is a framework to design distributed soft real-time systems based on timed plans. Timed plans - they define system workflow - contain actions to be executed by distributed components at specified times. The execution of a plan, however, has its costs, in terms of memory, power, bandwidth, and so on. Moreover, since plans may be modified to adapt system behaviour to environment conditions, they may need to be checked for coherency. This paper presents RTP extensions both to keep track (and take control) of factors impacting on system Quality-of-Service, and techniques to check timed plans validity through Petri Nets. With these extensions the system itself is able to control its own behaviour by analysing its past history and by tuning the future part of its timed plan while keeping internal coherency.