> Once the heap size gets larger than the threshold under which compressed references are working, a surprising thing happens: references suddenly become uncompressed
Am I correct in assuming that this is made possible because Hotspot can re-JIT? So the GC/Allocator just warns the JITter, "hey, all of your Oops [flags] code is no longer valid," resulting in a re-JIT of everything? Or a prologue in every method that checks the Oops flags (and triggers a re-JIT)?