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DbMpoolFile::set_priority |
#include <db_cxx.h>int DbMpoolFile::set_priority(DB_CACHE_PRIORITY priority);
int DbMpoolFile::get_priority(DB_CACHE_PRIORITY *priorityp);
Set the cache priority for pages from the specified file. 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 buffer pool. 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 calling the Db::get_mpf method.
The DbMpoolFile::set_priority method configures a file in the memory pool, 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 DbMpoolFile::get_priority method returns the cache priority.
The DbMpoolFile::get_priority method may be called at any time during the life of the application.
The DbMpoolFile::get_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.
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