V$LIBRARYCACHE contains statistics about library cache performance and activity.
| Column | Datatype | Description |
|---|---|---|
NAMESPACE |
VARCHAR2(15) |
Library cache namespace |
GETS |
NUMBER |
Number of times a lock was requested for objects of this namespace |
GETHITS |
NUMBER |
Number of times an object's handle was found in memory |
GETHITRATIO |
NUMBER |
Ratio of GETHITS to GETS |
PINS |
NUMBER |
Number of times a PIN was requested for objects of this namespace |
PINHITS |
NUMBER |
Number of times all of the metadata pieces of the library object were found in memory |
PINHITRATIO |
NUMBER |
Ratio of PINHITS to PINS |
RELOADS |
NUMBER |
Any PIN of an object that is not the first PIN performed since the object handle was created, and which requires loading the object from disk |
INVALIDATIONS |
NUMBER |
Total number of times objects in this namespace were marked invalid because a dependent object was modified |
DLM_LOCK_REQUESTS |
NUMBER |
Number of GET requests lock instance locks |
DLM_PIN_REQUESTS |
NUMBER |
Number of PIN requests lock instance locks |
DLM_PIN_RELEASES |
NUMBER |
Number of release requests PIN instance locks |
DLM_INVALIDATION_REQUESTS |
NUMBER |
Number of GET requests for invalidation instance locks |
DLM_INVALIDATIONS |
NUMBER |
Number of invalidation pings received from other instances |