Resolving the most common mutex issues is detailed in their respective Oracle internals chapter. For now, you are fully prepared to detect if mutex contention exists, if it is significant, and specifically which mutex is being requested.

Figure 3-18. An example of mutex contention. This situation was created by having a few sessions opening and closing a very simple cursor in a tight PL/SQL loop.

Figure 3-19. An example of mutex contention. This situation was created in the same way as the one reflected in Figure 3-18, except the instance parameter session_cached_cursors was set to zero. This ensures exclusive library cache mutex acquisition requests.