Comment by kaba0

It can remove a few increments/decrements (more like a single pair at inlining a function), but that’s not what makes it problematic.

If you do have a bigger object graph, not using it anymore will recursively go on and decrement the counters, removing potentially many objects from memory, totally killing the given thread’s cache/performance. All that is amortized with a tracing GC. On top, atomic counters are very expensive.

Of course you can probably get away with using (A)RC at few places at most with Rust, but if you decide to track object lifetimes with RC for loads of objects, it will have a price (which may or may not be worthy. In my opinion, it is better to stick to Rust for low-level programs)