[mlaretallack]

ive not done hard real time for a number of years (usually I have foubd its not needed), but Xenomai would be one option for real hard realtime. The other option is to use the rtlinux patches, however that is not true hard real time, but for most use-cases works ok.

[DenseComet]

Interesting, thank you! I'll take a look at Xemomai, but it seems like the options are very limited. I'm building a TVC rocket, so hard real time is unfortunately a strict requirement.

[Gibbon1]

I think you can do hard real time inside drivers. The other is some embedded linux capable chips have TPU's, aka Time Processing Units.

For something like a thrust vectoring rocket, I'd stick to a sub processor running an actual RTOS or bare metal code.

[p_l]

Xenomai might be fast enough with some coprocessing added if necessary. It makes your RT threads have essentially "normal" POSIX RT api, but runs them on separate kernel that can respond to things like interrupts much, much faster (including stable timeslicing)