D garbage collector and real-time systems

[Tom via Digitalmars-d]

What's the state of deterministic GC in D, or alternatively being
able to disable the GC?

I've been looking into languages to implement a real-time testing
system and had thought of D, but AFAICT the GC makes it
unsuitable.  The CGCD effort looks to be moving in the right
direction, but it would still be stop-the-world, just not for as
long as it used to.

Something like Lua's iterative GC would be better, as I think it
would give deterministic real-time latency alongside the GC (by
making the GC interruptible).  Are there any plans in this
direction?

Or is there now the possibility of disabling the GC altogether,
or replacing it with a refcounting 'GC' etc?