Locks and latches
The following views provide information about the status of locks and latches within the instance:
- *$ACCESS
Lists all locked objects in the database and the sessions accessing these objects.
- *$BUFFER_POOL
Provides information about the available buffer pools. The number of buffer pools is related to the initialization parameter DB_BLOCK_LRU_LATCHES.
- *$ENQUEUE_LOCK
Lists all locks owned by enqueue state objects.
- *$LATCH
Provides statistics for all latches. If the latch is a parent latch, provides a summation of the statistics for each of its children latches. Available after database is opened.
- *$LATCH_CHILDREN
Provides statistics for all children latches.
- *$LATCH_MISSES
Provides statistics about all failures to acquire a latch.
- *$LATCH_PARENT
Provides statistics for all parent latches.
- *$LATCHHOLDER
Provides information about current latch holders.
- *$LATCHNAME
Provides a decoded latch name for every latch listed in *$LATCH. Available after database is mounted.
- *$LOCK
Lists all locks held and all outstanding requests for locks or latches.
- *$LOCKED_OBJECT
Lists all objects currently locked by transactions within the system.
- *$RESOURCE
Contains the names, types, and addresses of all resources in the system.
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