How to debug an Apache failure running a Python Django app

I have a shared hosting that every few days, will just stop, and then restart after a period of time (like 45 minutes). If I catch it, I am able to start it again. But I am interested in trying to debug the problem and fix it as my site is now handling thousands of page views a day.开发者_StackOverflow

One thing I have noticed: it usually happens right after a user has uploaded an image. My app (Django + Python) uses 65 MB of memory but has gone over the 80 MB limit by the hosting company a few times (they send emails warning I will need to buy more). I am not sure if that helps but I'd love some advice on how to debug this and get my site running smoothly again.

[Wed Jun 08 10:53:46 2011] [error] Exception KeyError: KeyError(-1208527168,) in <module 'threading' from '/usr/local/lib/python2.6/threading.pyc'> ignored
[Wed Jun 08 10:53:46 2011] [error] Exception KeyError: KeyError(-1208527168,) in <module 'threading' from '/usr/local/lib/python2.6/threading.pyc'> ignored
[Wed Jun 08 10:53:46 2011] [error] Exception KeyError: KeyError(-1208527168,) in <module 'threading' from '/usr/local/lib/python2.6/threading.pyc'> ignored
[Wed Jun 08 10:53:46 2011] [error] Exception KeyError: KeyError(-1208527168,) in <module 'threading' from '/usr/local/lib/python2.6/threading.pyc'> ignored
[Wed Jun 08 10:53:46 2011] [error] Exception KeyError: KeyError(-1208527168,) in <module 'threading' from '/usr/local/lib/python2.6/threading.pyc'> ignored
[Wed Jun 08 08:53:46 2011] [error] Exception KeyError: KeyError(-1208527168,) in <module 'threading' from '/usr/local/lib/python2.6/threading.pyc'> ignored
[Wed Jun 08 10:53:46 2011] [notice] caught SIGTERM, shutting down