> I have read in just about every book I own that Perl handles garbage collection automatically

Being pedantic, Perl 5 does not have a garbage collector, it uses reference counting.
Few languages and run-time environments are capable of returning memory to the OS. Windows does allow so-called 'user-heaps', but I don't think many people use them. Even so Windows only allows whole unused pages (4kb/page on 32-bit Intel) to be returned to the OS, heap fragmentation is a common issue which will prevent this.
This does not happen automatically, the application (in this case, perl) has to call the API, usually HeapCompact.

In reply to Re: memory deallocation by cdarke
in thread memory deallocation by Nova

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