I've been forced to spend time troubleshooting Apache again recently. One cool tool I've been using this time is apache-top.

apache-top is a Python script which is meant to be run from a Unix command line.

You can run it like this:
python apache-top.py -u http://localhost/server-status
The output is very reminiscent of the Unix `top` command. The purpose of the output is to show you a quick Apache status and show you which Apache processes are causing the most load on your server.

The default display sorts the Apache processes by SS (Seconds since beginning of most recent request). Sometimes I use the 'C' key to sort the display by CPU utilization.

This is a pretty useful tool for getting a look "inside" Apache. It's an improvement over Apache's built in server-status and it's a handy addition to any web administrator's toolbox.