#include <db_cxx.h>

DbMpoolFile::set_priority(DB_CACHE_PRIORITY priority); 

Set the cache priority for pages referenced by the DbMpoolFile handle.

The priority of a page biases the replacement algorithm to be more or less likely to discard a page when space is needed in the cache. The bias is temporary, and pages will eventually be discarded if they are not referenced again. The DbMpoolFile::set_priority() method is only advisory, and does not guarantee pages will be treated in a specific way.

To set the priority for the pages belonging to a particular database, call the DbMpoolFile::set_priority() method using the DbMpoolFile handle returned by the Db::get_mpf() method.

The DbMpoolFile::set_priority() method configures a file in the cache, not only operations performed using the specified DbMpoolFile handle.

The DbMpoolFile::set_priority() method may be called at any time during the life of the application.

The DbMpoolFile::set_priority() method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.



The priority parameter must be set to one of the following values:


    The lowest priority: pages are the most likely to be discarded.


    The next lowest priority.


    The default priority.


    The next highest priority.


    The highest priority: pages are the least likely to be discarded.


DbEnv, DbMpoolFile

See Also

Memory Pools and Related Methods