Need to set up a new rule which fires an alarm when a specific amount of database sessions are locked.
Which metric can be used in the rule to get the amount of locked sessions?
The amount of locked sessions is stored in the metric num_of_exceeding_locks in DBO_Locks_History_Tree_Summary.
These are the locks which have been exceeded a predefined threshold (90 seconds by default). This threshold is configurable in "Collections Settings" of the Global Administration.