&gt; Because atomic reference counting has much worse throughput than tracing GC. This has been known for a long time.<p>I know this to be true for ubiquitously heap allocated systems, but I&#x27;m curious if this has been studied extensively for stack+heap reference counted systems, where only a relatively small number of items are heap allocated?  Seems like reference counting would gain in this kind of environment, as the stack effectively gives you many of the advantages generational gcs enjoy from their nursery, and you don&#x27;t have to worry about write boundaries, tracing and the like.