Comment Re:Seems like a rationalization (Score 4, Informative) 87
Look, that guy ("Required Snark") might have been an asshole, but you didn't really acquit yourself well either in your original post. I cofounded and work for a real-time telemetry contractor. We use Android, but the Linux kernel isn't built to handle read-time applications reliably. There are too many things to handle in terms of time-safe task-switching, execution, multi-processing, and internal consistency in order for it to be a good RTOS. So keeping that in mind, I had to implement a real time environment in userspace that uses root and some native code in order to collect data, send data, and operate hardware in a safe, timely manner. But this isn't the best solution because I still have to deal with the fact that it's all just a frustrating abstraction sitting on top of a kernel that isn't at all concerned with what I'm actually trying to do, despite my best efforts to single-handedly make the necessary changes.
Your "newer processors" bit is also completely off the mark. Radiation-hardened processors lag generations behind owing to the need for extensive redesign and testing. Complicating this picture is the fact that even then, they still have varying levels of reliability and power efficiency. You don't want a processor that has a microcode architecture that makes your targeted code difficult to semantically evaluate and verify. You don't want (or need) a recent processor that hasn't had extensive real-world user testing. You want a processor in the goldilocks zone, one that you've worked with before and has a community behind it.
Keeping that all in mind, they chose a good processor, and already had an OS largely built for it based on previous missions with earlier versions of the same processor.