Oracle Enqueues

The Enqueues Oracle metric are locks that serialize access to database resources. This event indicates that the session is waiting for a lock that is held by another session.

This query just shows sessions waiting for enqueue resources

SELECT sid, serial#, event, wait_class

FROM v$session WHERE event LIKE 'enq:%';

To get description of an enqueue resource use following query.


eq_name "Enqueue", "Enqueue Type",

eq.req_description "Description"

FROM v$enqueue_statistics eq, v$event_name ev

WHERE eq.event#=ev.event#