That's due to the memory policies of Perl. You undef a large hash, which means that for each value stored, Perl has to decrement the refcount of the value, check to see if it's zero, and if it's zero, free its memory (and possibly decrement other ref counters). Finally, it needs to free up the memory structure of the hash itself, which will be lots of linked lists, so there are lots of little pieces of memory to be freed.

Abigail

In reply to Re: freeing hashes on Linux by Abigail-II
in thread freeing hashes on Linux by hemantj

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