SHARED POOL V$LIBRARYCACHE STATISTIC NOTES:
Namespace - Library cache namespace (SQL AREA, TABLE/PROCEDURE, BODY, TRIGGER, INDEX, CLUSTER, OBJECT, PIPE)
Gets - Number of times the system requests handles to library objects belonging to this namespace
GetHits - Number of times the handles are already allocated in the cache.
If the handle is not already allocated, it is a miss. The handle is then allocated and inserted into the cache.
GetHit Ratio - Number of GETHITS divided by GETS. Values close to 1 indicate that most of the handles the system
has tried to get are cached.
Pins - Number of times the system issues pin requests for objects in the cache in order to access them.
PinHits - Number of times that objects the system is pinning and accessing are already allocated and
initialized in the cache. Otherwise, it is a miss, and the system has to allocate it in the cache and initialize it with
data queried from the database or generate the data.
PinHit Ratio - Number of PINHITS divided by number of PINS. Values close to 1 indicate that most of the objects
the system has tried to pin and access have been cached.
Reloads - Number of times that library objects have to be reinitialized and reloaded with data because
they have been aged out or invalidated.
Invalidations - Number of times that non-persistent library objects (like shared SQL areas) have been invalidated.
GetHit Ratio and PinHit Ratio should be > 70