Viewing output/debugging crashes with web.py/lighttpd/fastcgi?

[Brandon Hsiao]

I'm running web.py on lighttpd with fastcgi. Every few hours the site just crashes, and every page either doesn't load or shows 500 Internal Server Error. The server spawns several processes [1] and I have a hunch these are causing it, but I have no way of knowing how. How can I view lighttpd's output? I've checked error.log and access.log in /var/log but there's nothing there.

In general, what is the standard way of debugging such things with lighttpd?

[1] It's a game website and I have to spawn new processes to run matches.