Memory consumption

Hello,
 
I have severe memory problems with Eclipse, Version 5.5 #63:
 
After some execution of my program, I get for instance
 
[eclipse 5]: statistics.
.
shared_heap_allocated:  118038528 bytes
shared_heap_used:       11315984 bytes
.
.
 
so more than 100M, and looking at unix "top" confirms this.  First, I
called eclipse with the option -s 50M to limit the size of the shared
heap; second, I'm wondering what all this memory is used for.
 
My program dynamically creates, uses, and erases a specific module many
times.  The module has a fixed interface predicate, but each time a few
internal predicates (which themselves are generated by the ech library)
are different.  Currently I write the module onto a stream and use then
compile_stream.
 
 
I understand that loading a module erases a previous version of it, but
one explanation for the memory consumption above could be that the dead
module's memory remains allocated.
 
What can I do?
 
Sebastian