12. GC Process
● GC finds non-reachable objects and adds
them to Free List
● If Free List is still empty, another Heap
allocated
13. MRI GC
● “Conservative”: any bit pattern could be a
pointer (may produce false positive)
● “Stop the world”: no other Ruby code can
execute during GC
● “Mark & Sweep”:
mark all objects in use, than sweep away
unmarked objects