V$GLOBAL_BLOCKED_LOCKS displays global blocked locks.

Column Datatype Description
ADDR RAW(4 | 8) Address of lock state object
KADDR RAW(4 | 8) Address of lock
SID NUMBER Identifier of session holding the lock (number)
TYPE VARCHAR2(2) Resource type (char)
ID1 NUMBER Resource identifier #1 (number)
ID2 NUMBER Resource identifier #2 (number)
LMODE NUMBER Lock mode held (number)
REQUEST NUMBER Lock mode requested (number)
CTIME NUMBER Time since current mode was granted