I believe the message is just informative. Being "internal use", console messages are not particularly well thought out (case in point, the crappy format of the warning messages).
My recollection is for B/S memory manager uses reference counting + GC, just like Python. This way simple objects get released right away when de-referenced (to 0), where orphaned cyclic structures get reaped by the Grim Collector on exit or low-memory condition. I think that makes for more acceptable behavior when dealing with humans on low memory/CPU devices vs periodic freezes from JVM/Android. And this particular GC tends to be a crank, muttering under breath while brooming