* Determine the problematic latch or mutex. With rare exception, the best solutions are latch- and mutex-specific, which means they are not general, but target a specific latch or mutex. Knowing the contention exists is not enough for a pinpoint diagnosis. You need to determine specifically which latch is the problem. Again, Oracle's wait interface provides us with this information.

* Understand why the latch or mutex is being requested so often. Ask yourself, "Why is the latch so popular? Why are processes so interested in acquiring this specific latch?" Answer the question, and try to discover how you can influence the situation so the latch is not being requested so often. To do this, you must understand Oracle's general serialization algorithm, the specific latch with contention issues, and the underlying memory structure and associated Oracle kernel code. The underlying memory structure and associated Oracle kernel code for the most common latching issues are presented in Chapters 6, 7, and 8, which cover Oracle internals.

* Understand why the latch or mutex is being held so long. Ask yourself, "Once the latch has been acquired, why is Oracle holding it so long?' Answer that question, and then ask yourself how you can influence the situation to reduce the time the latch must be held. As with the previous point, answers to this question are the focus of Chapters 6, 7, and 8.