There's lots of interesting key differences between something based on Linux, for example, and QNX. Worth digging into if you're interested in these things. My colleague wrote a short ebook and the intro has a good summary: https://gitlab.com/elahav/qnx-rpi-book/-/tree/master/pdf
https://ethw.org/Milestones:TRON_Real-time_Operating_System_...
which was demoed running on an 80186 with _multiple_ windows running videos w/o dropping a frame.
Described as "The most installed operating system in the world":
https://www.linuxinsider.com/story/the-most-popular-operatin...
Unfortunately, the U.S. State Department viewed the Japanese plan to place it on all computers in their educational system as anti-competitive.
Really wish it was available for the Raspberry Pi.
Can you recommend books or papers on how the kernel works, and what makes it better than e.g. L4/sel4 or Mach?
These machines didn't work at all without a server to network boot from, aka the LEXICON machine, so it's not likely some teacher squirreled all that across the border.
They were not commercially available.
I would seriously doubt that QNX or anything like it resembling a "real OS" is running on the automatic transmission. If the transmission controller is running any OS at all it's likely a microcontroller running a much more specialized RTOS.
QNX is very common in automotive applications, but in things like digital instrument clusters and ADAS where the software is complex enough to benefit from a full networkable OS with support for a lot of different high speed buses but the use case still needs real-time guarantees and/or microkernel stability. I've specifically seen QNX's hypervisor marketed for digital clusters where the critical data display and interaction with the ECU could happen within a fully certified QNX environment that would be designed to be as stable and reliable as possible while allowing infotainment applications to run in a VM instance of Android, Linux, or even more QNX where software reliability was less critical. If it crashes, the important instruments are still working.
Ford's "Sync 3" and "Sync 4/4A" infotainment systems run on QNX as well, though being just infotainment they didn't really care about the realtime aspect (though I'm sure stability was a big thing compared to their Windows CE based predecessors). They've moved to Android for their latest revision.
I've got a Sync 2 car, and I can't say I've noticed instability. The UI toolkit is slow, but the story on that is someone's cousin did something some Macromedia stuff that barely worked and they shipped that. I've got some issues with GPS offset, but that's pretty stable. I had worse stability with the Chrysler UConnect in my 2017 Pacifica, and that was reportedly based on QNX; it would sometimes crash and restart, or the screen would not come on at all unless you knew the magic buttons to hold to force reboot.
Whatever version of MFT my car shipped with was pretty bad, hitting the category button in the satellite radio controls was about a 1/5 chance of a crash. It also wasn't great at handling my USB drive full of MP3s. A few months later an update came out that was actually never officially released for my car, but if you put the right files on the USB drive it installed just fine. After that update those crashes were gone. All that was left, and it happened until I upgraded the system, was maybe once every 2-3 months the Bluetooth stack crashed and took the entire media UI with it, I'd have to use the physical Source button to switch to AM/FM and then switch back to regain control though whatever was playing would keep working.
I upgraded to Sync 3 and haven't crashed it since. Sometimes it gets in a fight with my wireless android auto adapter, but it's never had an issue in wired mode which is all it officially supports so I'm not going to fault it there.