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by nullnilvoid 3334 days ago
Interesting. I would like to know the comparisons between Fuchsia, and QNX which is also a real-time microkernel operating system that runs on cars and phones. It seems Fuchsia competes with QNX directly in that space.

Another question is if the operating system is designed to be real-time, the applications also need to be real-time. If the applications are not real-time, you lose the real-timeness. Dart is garbage-collected. I suppose it is not real-time, yes?

1 comments

There are a bunch of hard realtime kernels; QNX is not a major player.
There's a bunch of them, but you'd never want to run hard realtime on a phone or tablet. Hard realtime gives you horrible performance, but excellent latency guarantees. One big thing they do in hard realtime systems is to disable the CPU cache, because caching prevents determinism. It's also essential for performance, but in a hard realtime system performance isn't important.
What are some of the major players?
VxWorks, eCos, ITRON, RTEMS, RTX... There are a plethora of players emphasizing specific features. Outside realtime, various BSDs and then some RT Linux and even still wince.

Free software plays a huge role in this field of course, dating back to the Cygnus days.