Improving the real-time behaviour of a multithreaded Java microcontroller by control theory and model based latency prediction

Abstract

Our aim is to investigate if it is possible to control and to stabilize the throughput (IPC rate) of a thread running on a multithreaded Java processor by a closed feedback loop and a model based latency predictor. We implemented a PID controller and a model based latency predictor in the processor simulator of the Komodo microcontroller developed at the universities of Karlsruhe and Augsburg to simulate both as additional hardware modules. GP (guaranteed percentage) scheduling is used to control the thread. Evaluations show that the aimed IPC rate of a thread is achieved by the controller and stabilized by the latency predictor thus improving the real-time capabilities of the Java processor.