When passing the hash back to the calling function, the process 
stalled indefinitely but there was a great deal of memory usage 
in the background and one CPU saturated.
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First, please don't put your entire posts into <c></c> or <code><code> tags. These are reserved for code.

Second, you are probably passing the hash back like that

    return %hash;
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which passes back a long, long, really long list of tuples (key/value pairs). Pass back a reference.

    return \%hash;
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See perlref.