[Vm-dev] What is meant by 'shrink' in the VM parameters?

I'm wondering what 'shrink' means in the following VM parameter comments:

"24 memory threshold above which shrinking object memory (rw)"

and

"32 number of shrink memory requests (read-only)"

My first thought is that a shrink represents Squeak release memory back to the operating system once it is no longer needed.

As I've mentioned before we are trying to reduce the RAM footprint of the www.squeak.org process and are watching various related figures.

We can see the value in VM parameter 32 increase, but while the value for parameter 3 (end of memory) goes down as you would expect, the operating system's view of the memory usage does not change.

Ken