Is there anything missing that compiling with -DDEBUGGING would add?

Yes, if your perl had been built with -DDEBUGGING, Devel::Leak would call its (then available) routine sv_dump() on the things in question, which would produce output similar to what you'd get with the module Devel::Peek. How much that helps, though, will depend on the particular situation...

Anyhow, most problems with memory leaks in Perl code are related to circular references. Consider the following 

for (1..1000000) {
    my $h = {};
    $h->{myself} = $h;
}

[download]

This harmlessly looking piece of code consumes about 130MB (on my machine). Reason is that the anonymous hashes (referenced by $h) are not being freed, because they're holding a reference to themselves, so their reference count doesn't drop to zero when the $h goes out of scope...

In reply to Re: understanding devel::leak by almut
in thread understanding devel::leak by nonnonymousnonk

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