ASA SQL User's Guide
Monitoring and Improving Performance
Using the cache to improve performance
On Windows NT/2000/XP and Windows 95/98/Me, the database server evaluates cache and operating statistics once per minute and computes an optimum cache size. The server computes a target cache size that uses all physical memory currently not in use, except for approximately 5 Mb that is to be left free for system use. The target cache size is never smaller than the specified or implicit minimum cache size. The target cache size never exceeds the specified or implicit maximum cache size, or the sum of the sizes of all open database and temporary files.
To avoid cache size oscillations, the database server increases the cache size incrementally. Rather than immediately adjusting the cache size to the target value, each adjustment modifies the cache size by 75% of the difference between the current and target cache size.
Windows 2000, Windows XP, and Windows Server 2003 can use Address Windowing Extensions (AWE) to support large cache sizes by specifying the -cw command-line option when starting the database server. AWE caches do not support dynamic cache sizing.
For more information, see -cw server option.