Weekend Reading: Troubleshooting the Linux kernel with Tanel

In this post by Tanel Poder, he lays out very simply how one can use general commands to find out what is going on with a Linux process.  No stack dumps required, no exotic debuggers, or other tools required.  I read this months ago, and flagged it for use later because I'm looking forward to using it.  Yes, I want to have a problem in our environment so I can troubleshoot it with these techniques.  :}