It is perhaps1 code like this: 

$self->[0] = \%h;

[download]

from Tie::Persistent that is making a circular reference. And a circular reference would mean that nothing tied to that module ever gets destroyed (prior to global destruction). (Or the module could be squirreling away a reference to your hash or to the 'tie' object in some other spot even without a circular reference.) Next step: Augment your simple example above with code that shows that the destruction isn't happening when it should and report that to the module author.

1 Wild guess, really. I didn't study the code long enough to understand it. I was just scanning for something like the above which your report made me highly suspicious of existing.

- tye        

In reply to Re^5: modularization, memory usage and performance (circles) by tye
in thread modularization, memory usage and performance by jmagiera

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