However, it was conceived for extensibility and flexibility in general, in the spirit of [6]. It has been used also for scripting CPU frequency scaling, debugging, application sandboxing among others [7,8].
Potentially, yes. However, I didn't try it. You could even disable GC completely. Lunatik provides some facilities that could be useful in this scenario as well, such as RCU tables and shared objects. For instance, you could pre-allocate the entire memory to be used by your Lua states and treat them as volatile. In this case, you could persist state on the shared objects stored and synchronized through a RCU table. Of course, you could implement your own GC or tune the existent GC modes as well.
I'm currently working on updating XDPLua for using kfuncs on top of the newest version of Lunatik.. I've a PoC already and should create a PR in a few weeks.