Comment by torginus

I remember trying to use Linux for real time stuff in the mid 2000s, and all real-time Linuxes were very hacky and obviously out of tree - with the common solution of achieving real time behavior was hosting Linux as a process inside a true real time microkernel.

Afaik, the reason why real time Linux was considered impractical was to have hard RT guarantees, you needed to ensure that ALL non-preemptable sections in the kernel had bounded runtime, which was a huge burden for a fairly niche use case.

I wonder how they got around this requirement, or if they didn't, did they rewrite everything to be compliant to this rule?

Also, does this means that Linux supports priority inversion now?