Implementation of Dynamic Round Robin Scheduling on Bare-Metal Shallow Multi-OS for Lightweighted Microcontrollers

In recent years, there has been a trend towards integrating functions using a small number of microcontrollers instead of employing multiple microcontrollers across various environments. This shift underscores the need for a hypervisor capable of efficiently utilizing resources while imposing minimal overhead. Addressing this demand, this paper introduces a hyper-visor employing dynamic round-robin scheduling, which flexibly adjusts time quantum allocation based on the urgency of each OS. Furthermore, a monitor mode is devised to oversee resource allocation among multiple OS. To enhance responsiveness while managing these OS, ultra-light context-switching is implemented within the monitor mode. The proposed system demonstrates a notable reduction in execution time, approximately 19% compared to traditional round-robin scheduling. Additionally, in terms of energy efficiency, the proposed system yields a 34% reduction in energy consumption compared to existing methods. Notably, the ultra-light context-switching mechanism consumes only about 5% of the processing cycle when compared to FreeRTOS.