Scheduling policy costs on a JAVA']JAVA microcontroller

This paper presents the implementation of different scheduling policies on a Java microcontroller. Seven new instructions were added to the architecture to support context switching and scheduler implementation. By using these instructions, four schedulers following the POSIX standard were developed for the specific architecture. These schedulers were used in a study about the impact of different scheduling policies for embedded systems applications. Several design costs are discussed, including the hardware cost of the extended instructions, ROM and RAM capacity used, the number of cycles to run the chosen scheduler and the application, and also the power consumption overhead. Experiments show that the exploration of different scheduling alternatives as well as careful scheduler implementation may play an important role in performance optimization.