Summary
Most database administrators are handed an application or a database and instructed to make it go faster. There's no documentation, no SQL activity rates, nothing. The DBA needs to use the monitoring facilities available to discover the tuning opportunities. Learn which tables are most frequently read and assign them to their own tablespaces. Pair synchronously read tablespaces with bufferpools that are intended to have random access, and tablespaces that are heavily asynchronously read with bufferpools that are intended to have prefetch access. Prefetch bufferpools need to be large enough to accommodate the demand, while random bufferpools should seek to minimize physical I/O rates via size increases until either (1) system paging occurs, or (2) the point of diminishing returns is reached.
In this chapter, bufferpools were introduced and their purpose described. Creating, altering, dropping, and monitoring bufferpools was discussed, in conjunction with monitoring tables and tablespaces. Several important formulas for evaluating tablespace and bufferpool performance were presented, and techniques for tuning tablespaces were discussed.
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