Get memory usage report from GC

[tcak via Digitalmars-d-learn]

Is there any way (I checked core.memory already) to collect 
report about memory usage from garbage collector? So, I can see a 
list of pointer and length information. Since getting this 
information would require another memory area in heap, it could 
be like logging when report is asked.

My long running but idle program starts using 41.7% of memory 
(that's close to 3GB), and it is not obvious whether the memory 
is allocated by a single variable, or many variables.