The G1PrintHeapRegions parameter generates a trace of which regions are allocated and which are collected. It'd be nice if we are able to "replay" the region allocation / reclamation based on such a trace. However, currently we are unable to as the trace is incomplete. These are the reasons why:
- There is no information on which regions are reclaimed during cleanup.
- There is no humongous region alocation information.
- After a full compaction, the heap is drastically restructured all the information of regions that were allocated up to that point is invalidated.
In addition we should make the output more consistent than it is now.