I don't get the GC. (heapSizeFactor followup)

[Richard (Rikki) Andrew Cattermole]

Right goal, wrong questions.

The process memory consumption may not be what the GC is consuming. You 
need to measure that first before questioning if the GC is the one doing 
it wrong.

For instance a badly acting buddy allocator in malloc could double 
memory like you're seeing. So swapping malloc may give the results you 
desire. But first rule out the GC.