in reply to
Memory usage of array and hashe variables by multiple inclusion.
A common cause of memory-leaks in Perl are circular references, whereby references among objects form a “loop” such that the reference-count to the members of the structure never returns to zero and so the memory never gets reclaimed.
Having “one thing in more than one place” is not a problem ... that’s just an object with multiple references to it ... so long as you arrange things such that, when an object is no longer required, all references to it go away.
The “virtual memory size” as seen by an operating system does not know anything about the in-use/free status of individual objects as seen by Perl.