You can use arenas for the cases where you really can't do without delayed/batched deallocation. But deterministic deallocation as provided by RC is a very good default for many cases, including where low-latency is a goal.

RC is not deterministic. That's the whole thing - when you free a refcounted object, you do not deterministically know how long is it going to take, and on systems that try to avoid RC-induced pauses, you don't get to know when the memory is going to be released.

If you want to talk determinism, you need to actually invest into deterministic behaviour - something that either requires dropping dynamic memory allocation altogether, or tends to go for GC with known determinism guarantees (for example, IBM Metronome).

Well, naive code is going to suck, be it RC or GC

> And despite what some people think, malloc/free are not O(1) free lunch

Of course. Be it through a GC allocator or not. If you're at the point where the allocator is giving you trouble then GC/RC is the least of your problems ;)