* Determine multiple resolution strategies. Surprising to most DBAs is that once the preceding points have been addressed, you will actually be able to arrive at multiple solutions. And these solutions will not be guesses or even good guesses. They will absolutely impact performance for the better!

* Take appropriate action. This step deserves its own bullet point because usually one of the solutions involves changing a hidden instance parameter, which typically requires the Oracle instance to be cycled. I don't take this lightly. Most production system nowadays can't simply be cycled. You will need to prioritize the solutions and plan their implementation based on expected performance improvement and uptime requirements. Quantitative solution analysis is the focus of Chapter 9 and also OraPub's Advanced Oracle Performance Analysis class.

As you can see, understanding how Oracle latches and mutexes work is just the beginning. But it is where you must start to resolve the most notorious of all Oracle performance problems, so it's worth spending your time to dig deep into the details.