I just hit this and thought I would share.

I have been debugging this for way too long and this is the results!

Situation: One of my apps (Windows service no less) is leaking 4k of memory at a indeterminate rate.

Cause: foreach $session (%SESSIONS)

In this loop I evaluate the session info in the hash key and decide if the session is still valid, if it is not I kill the session and delete the $session key of the hash. Look ok so far?

Wrong! every time through the loop I leaked 4k for every past deleted session!!! the delete was not acting on the key, the data in the keys was gone but there were still keys around

Fix: foreach $session (keys %SESSIONS)

I'm not sure why I was leaking every time through the loop, however there may be reasons I don't know about, but folks, WATCH THE KEYWORDS! this took quite a while to debug just because it LOOKED right. If someone knows why this would leak mem (I was only evaluating the data in the hash, the only changes to the hash was when I would try to delete a key) I would love an explination.

"Nothing is sure but death and taxes" I say combine the two and its death to all taxes!

In reply to Newbie(and notso newbie?) warning! by Rex(Wrecks)

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