Towards hierarchical scheduling in VxWorks

Over the years, we have worked on hierarchical scheduling frameworks from a theoretical point of view. In this paper we present our initial results of the implementation of our hierarchical scheduling framework in a commercial operating system VxWorks. The purpose of the implementation is twofold: (1) we would like to demonstrate feasibility of its implementation in a commercial operating system, without having to modify the kernel source code, and (2) we would like to present detailed figures of various key properties with respect to the overhead of the implementation. During the implementation of the hierarchical scheduler, we have also developed a number of simple task schedulers. We present details of the implementation of Rate-Monotonic (RM) and Earliest Deadline First (EDF) schedulers. Finally, we present the design of our hierarchical scheduling framework, and we discuss our current status in the project