Resolving The Free Buffer Waits Event

If you enjoy solving a difficult technical puzzle, then working on a system plagued by free buffer waits should get your adrenaline pumping! The free buffer waits event is intriguing because it takes a combination of database writer, IO subsystem, SQL, buffer cache configuration, and server process activity to manifest. Understanding this wait event is fascinating because it touches the very deepest parts of the Oracle architecture; the least recently used lists, the dirty lists, how blocks are brought into the buffer cache, and buffer "movement." Fortunately, with so many causes to this problem there are also many solutions. This presentation focuses squarely on resolving free buffer waits by focusing on Oracle buffer cache internals, diagnosis using Oracle's wait interface, and solution development focusing on tweaking Oracle, the application (including the SQL), and the IO subsystem. This is a very practical yet deep internal presentation, filled with amazing discoveries about how Oracle works.