On the schedulability analysis for distributed hard real-time systems

We investigate into the validity of the rate monotonic analysis techniques for distributed hard real time systems. A recent paper has shown that the algorithm developed by K. Tindell and J. Clark (1994) for the analysis of this kind of system was incomplete because it did not test all the possible cases. We prove that the algorithm is valid as it is stated and that it effectively obtains an upper bound for the worst case response times to external events in distributed systems, since the longest response always occurs within the cases that are currently tested by this algorithm. In addition, we extend the analysis technique to determine an upper bound for the local response times of particular actions in a response to an event, thus allowing the definition and verification of local deadlines for elementary actions in distributed systems.