Incremental rate monotonic scheduling for improved control system performance

The paper presents an algorithm and its run-time performance for scheduling periodic incremental and design-to-time processes. The algorithm is based on the slack stealer which dynamically answers the question "how much execution time is available prior to a deadline" when all periodic processes are scheduled using rate monotonic scheduling. An incremental process asks how much execution time is available after the baseline component has completed and prior to the execution of a process increment. A design-to-time process asks how much execution time is available before the process begins execution and selects a version which gives the greatest precision in the available time. For both incremental and design-to-time processes, a minimum amount of time is statically reserved so that an acceptable but suboptimal solution will always be calculated. The author identifies and proposes a solution for the practical problem of supporting criticalities when scheduling slack and analyze the run-time overheads of this algorithm. The analysis is applied to two real-world data sets. In certain cases, the execution time of this algorithm is found to be efficient.