The canonical examples have already been given, but for a practical example, try something like:
  
sub make_a_leak {
  my $tree = HTML::TreeBuilder->new();
  $tree->parse($some_big_html_file);
  return;
}

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Without a call to $tree->delete, the above code will snarf tons of memory, because of all the circular references contained within the TreeBuilder parse-tree. 
   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

In reply to (MeowChow) Re2: Looking for Leaks by MeowChow
in thread Looking for Leaks by MeowChow

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