Identifier:db2.conn_pkg_cache_hit_ratio
Database Object Monitored:Connection
Category:Buffer Pool and I/O
Description:Package cache hit ratio (percent effective)
Equation:100 * (1 - (connection.pkg_cache_inserts / connection.pkg_cache_lookups))
Usage Notes:The package cache hit ratio tells you whether or not the package cache is being used effectively. If the hit ratio is higher than 80%, the package cache is performing well. A lower value may indicate that the size of the package cache (pckcachesz) should be increased.
You will need to experiment with the size of the package cache to find the optimal number for the pckcachesz configuration parameter. For example, you might be able to use a smaller package cache size if there is no increase in the pkg_cache_inserts data element when you decrease the size of the cache. Decreasing the package cache size frees up system resources for other work. It is also possible that you could improve overall system performance by increasing the size of the package cache if by doing so, you decrease the number of package cache inserts.
| Note: | For multiple buffer pools, the data is combined and only the aggregate number is returned. |