I am examining a case for a new RT/embedded OS in today's situation. I would like to get a simple YES/NO answer from embedded developers.
Suppose that you are starting a new project. You are considering to use embedded Linux and you offered an RT/embedded OS by a vendor John Doe Inc. The RTOS is proposed in complete source code, uses GNU toolchain to build and development license is free. Production license cost is negligible for your purpose and support costs the same as support from embedded Linux vendors. In other words, John Doe's offer comes even to embedded Linux with regard to source code, development and license costs.
Let's also suppose that John Doe's RTOS offers come even with Linux in ready code availability (John Doe Inc. ported to its OS open-source libraries that you need).
Now you have to consider pros and cons of the new RTOS option compared to Linux (we assume that you know Linux pros and cons pretty well).
* Smaller footprint, better configurability
* More system resources left free
* Better performance of OS kernel and services
* Real-time responsiveness
* Simpler build and maintenance
* Simpler programming
* Worse support (supported only by John Doe Inc. and its distributors, no match to Linux community)
* Established bad reputation of dedicated RT/embedded OSes
The question is: would you give a try for John Doe's RT/embedded OS?