Real-time safe GC algorithms and data structures provide strong guarantees that any interruptions to the running program caused by GC activity will have a bounded duration, with strong guarantees on the upper bound of any pause. This is important in latency sensitive software and real-time software that needs to meet deadlines.
Thanks for the ORCA link. I'll have to study it more closely but from Fig 17 it looks to have quite unpredictable jitter up to at least 20ms. Which is obviously fine for many things but not useful for other things (e.g. processing AVB streaming audio packets at line rate every 125 us).
As with all things, we should use the correct language / runtime for the domain problems it's designed to solve.
The pony runtime makes other decisions (such as non-preemptable schedulers) which would have more of an effect on your use-case methinks.
Thank you for the discussion and your interest!