You can use SQL Anywhere to automatically resize the database cache while the database server is running. With full dynamic cache sizing, the cache grows when more memory is made available to the database server and shrinks when cache memory is required by other applications. The effectiveness of dynamic cache sizing varies depending on the operating system and the amount of available physical memory.
Typically, the cache requirements are assessed by dynamic cache sizing once per minute. However, when a new database is started or when a file grows significantly, the assessment frequency may increase to once every five seconds for thirty seconds. After the initial thirty second period, the assessment frequency returns to once per minute. File growth is considered significant if it is one eighth greater than the last growth that triggered an increase or one eighth greater than when the database started.
With dynamic cache sizing you do not need to explicitly configure the database cache.
If you attempt to set your initial or minimum cache sizes to a value that is less than one eighth of the maximum cache size, the initial and minimum cache sizes are automatically increased relative to the maximum cache size.
When an Address Windowing Extensions (AWE) cache is used, dynamic cache sizing is disabled. Only the 32-bit Windows database server can use an AWE cache.
The use of AWE is deprecated. It is recommended that you use the 64-bit version of the SQL Anywhere database server on a 64-bit Windows operating system if you require a large cache.
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