Young Generation Heap Layout

[Blair Archibald]

Hi,

I'm experimenting with new methods of performing heap resizing (like
Ergonomics/Adaptive size policy but with different principles/techniques).

I'm working mainly with the ParallelScavenge GC/Heap and was wondering if
there is a particular reason that the young generation needs to be in the
form:

Eden | To | From

I would like to do some (fairly aggressive) Eden resizing so it would be
beneficial to have a young generation as follows:

To | From | Eden

This provides the possibility of scaling the generation to provide free
space at the end of eden. When I tried this however I got various issues
with CompressedOOPs and when running without CompressedOOPs I get strange
segfaults.

Are there any particular areas where this space layout invariant needs to
be enforced? Would it ever be possible to have a layout with eden at the
end?

Many thanks,
Blair