Open source FreeRTOS as a case study in real-time operating system evolution

•Propose qualitative and quantitate benchmark suit for RTOS test.•Perform performance tests and behavior tests to character FreeRTOS evolution process.•Draw conclusions related to FreeRTOS's evolution which can be useful for the FreeRTOS group, other RTOS developments, and RTOS users.

This paper studies the evolution of a real-time operating system, the open source FreeRTOS. We focus on the changes in real-time performance and behaviour over the last ten years. Six major release versions are benchmarked, presenting quantitative and qualitative development trends. We also use the available source code to discover the reasons for the changes. By analysing the results, we draw some conclusions related to this RTOS’s evolution which can be useful for the FreeRTOS group, other RTOS developments, and also RTOS users.