Performance Schema Lock Tables The Performance Schema maintains  metadata_locks  table content as follows, using the  LOCK_STATUS column to indicate the status of each lock: •When a metadata lock is requested and obtained immediately, a row with a status of  GRANTED  is inserted. •When a metadata lock is requested and not obtained immediately, a row with a status of  PENDING  is inserted. •When a metadata lock previously requested is granted, its row status is updated to  GRANTED . •When a metadata lock is released, its row is deleted. •When a pending lock request is canceled by the deadlock detector to break a deadlock ( ER_LOCK_DEADLOCK ), its row status is updated from  PENDING  to  VICTIM . •When a pending lock request times out ( ER_LOCK_WAIT_TIMEOUT ), its row status is updated from PENDING  to  TIMEOUT . •When granted lock or pending lock request is killed, its row status is updated from  GRANTED  or  PENDING to  KILLED . •The  VICTIM ,  TIMEOUT , and  KILLED  status values are brief and signify that the lock row is about to be deleted. •The  PRE_ACQUIRE_NOTIFY  and  POST_RELEASE_NOTIFY  status values are brief and signify that the metadata locking subsubsystem is notifying interested storage engines while entering lock acquisition operations or leaving lock release operations. The  metadata_locks  table has these columns: • OBJECT_TYPE • OBJECT_SCHEMA • OBJECT_NAME • OBJECT_INSTANCE_BEGIN • LOCK_TYPE The lock type from the metadata lock subsystem. The value is one of  INTENTION_EXCLUSIVE , SHARED ,  SHARED_HIGH_PRIO ,  SHARED_READ ,  SHARED_WRITE ,  SHARED_UPGRADABLE , SHARED_NO_WRITE ,  SHARED_NO_READ_WRITE , or  EXCLUSIVE . The address in memory of the instrumented object. The name of the instrumented object. The schema that contains the object. A value of  USER LEVEL LOCK  indicates a lock acquired with  GET_LOCK() . A value of  LOCKING SERVICE  indicates a lock acquired with the locking service described in Section 5.6.9.1, “The Locking Service” . The type of lock used in the metadata lock subsystem. The value is one of  GLOBAL ,  SCHEMA ,  TABLE , FUNCTION ,  PROCEDURE ,  TRIGGER  (currently unused),  EVENT ,  COMMIT ,  USER LEVEL LOCK , TABLESPACE , or  LOCKING SERVICE . 5028