The more memory you can acquire for your computer system, the better. In fact, adding memory is typically the best way to improve performance. In addition to Oracle’s using memory for the System Global Area, the operating system will use memory to track each process and handle disk I/O. For detailed information about how Oracle uses memory, see Chapter 10. You want sufficient memory to allow the entire SGA to remain in memory without causing swapping and paging. A rule of thumb is that your system memory should be at least three times the size of the SGA.

Of course, adding memory is only the first step; Oracle must be configured to utilize the additional memory—for example, by adding additional database buffers or shared pool. See Chapter 3, for more information.