RFR: 8274178: Occupancy value in logging and JFR event is inaccurate in G1IHOPControl

[Jonathan Joo]

Hi Thomas,

Thanks for taking a look! I just wanted to clarify what you meant from your
message - for the field that I'm replacing ("occupancy"), are you saying
that we do indeed want to look at the total used heap space, even though
get_conc_mark_start_threshold() is depending on the non_young occupancy
bytes? In other words, the actual_target values being logged are related to
heap()->used(), while the get_conc_mark_start_threshold() values are
related to non_young_capacity_bytes()?

If so, would an appropriate change be something like keeping the original
code, but adding a single new field in the debug message after "threshold"
with something like: "non-young usage (compared against threshold): " +
G1CollectedHeap::heap()->non_young_capacity_bytes()?

Thank you,

~ Jonathan