On the performance of open-source RTOS synchronization primitives

Contemporary embedded system development is focusing more and more on software modularity and reuse, to reduce development costs and improve reliability. In this scenario, a Real Time Operating System (RTOS) often plays a central role to schedule task execution and provide inter-task communication and synchronization. For this reason, its performance and overhead become critical points of system design and evaluation. In this paper the basic performance of FreeRTOS, an open-source RTOS widely adopted for low-cost applications, is evaluated experimentally. The areas considered in the evaluation include context switch and semaphore synchronization overheads, as well as task activation jitter unduly induced by lower-priority tasks.