Detecting Memory Leaks

[sam at machine15.com (Samuel Donham)]

Hi everyone,
Normally, I wouldn't ask for help with work-related problems, but I'm out
of ideas.  If anyone can provide a reasonable answer to this, I'm bringing
a stack of free pizzas to the next BLU meeting.

One of my clients claims that I have a memory leak in one of our
applications.  He claims that 'top' reports my app is slowly consuming
more memory after running for 30 days (now 20 megs, up from 8 when it was
first started).  Perhaps there is a memory leak, but I don't think 'top'
is a good indicator of one ('free' would be much better).  In addition,
I've searched high and low for the leak with no success.  I've also run
Valgrind (http://valgrind.kde.org) on my app, with no report of a leak.

My question is, does anyone have any creative ideas to prove that a leak
does NOT exist?  It's far easier to prove that one does exist than to
prove it does not.  Knowing that the memory will likely be released after
some time, I need to prove this but it will take months for the app to run
in order to so.  I would like to limit the amount of memory the app is
allowed to consume.  I've tried using 'ulimit,' but the app repeatedly
goes over the limit (soft and hard).  Using '/etc/security' may work, but
I'm reluctant to try for it's on a per-user basis, and I would like a
per-process basis.

Any ideas?  What's YOUR favorite means of detecting memory leaks?  Lastly,
what kind of pizza/soda  do you like?
Any help would be greatly appreciated.  Thanks guys, see you at the next
meeting.
-sam