The greater the percentage of time that the buffer is used, the lower the percentage of time the disks are used. Since memory is faster than disks, you will get better performance with a better buffer hit percentage. For example, a 90 percent buffer hit percentage equates to 10 disk reads for every 100 requests to the database manager. If you increase your buffer hit percentage to 95 percent, you are only doing 5 disk reads for the same number of requests, which is a 50 percent reduction in requests to the disk. A small change in buffer hit percentage can equate to a large reduction in disk I/O. This is especially noticeable at the high end; changing from 95 percent buffer hit percentage to 96 percent represents a 20 percent reduction in disk I/O.