Number of buffers

Pick an appropriate number of buffers of each size so buffers are available for use when they are needed, an optimum amount of data is kept in virtual storage during application program processing, and application program wait time is minimized.

The trade-off in picking a number of buffers is that each buffer uses up virtual storage.

When you initially choose buffer sizes and the number of buffers, you are making a scientific guess based on what you know about the design of your database and the processing requirements of your applications. After you choose and implement buffer size and numbers, various monitoring tools are available to help you determine how well your scientific guess worked.

Buffer size and number of buffers are specified when the system is initialized. Both can be changed (tuned) for optimum performance at any time.