LOCK_USAGE
Provides aggregate information about lock requests, releases, and attempts, such as wait time/count and hold time/count. Vertica records:
- Lock attempts at the end of the locking process
- Lock releases after lock attempts are released
| Column Name | Data Type | Description |
|---|---|---|
NODE_NAME |
VARCHAR |
Name of the node that is reporting the requested information on which lock interaction occurs. |
SESSION_ID |
VARCHAR |
Identifier for this session. This identifier is unique within the cluster at any point in time but can be reused when the session closes. |
OBJECT_NAME |
VARCHAR |
Name of object being locked; can be a table or an internal structure (projection, global catalog, or local catalog). |
MODE |
VARCHAR |
Intended operations of the transaction. Otherwise, this value is NONE. For a list of lock modes and compatibility, see Lock Modes. |
AVG_HOLD_TIME |
INTERVAL |
Average time (measured in intervals) that Vertica holds a lock. |
MAX_HOLD_TIME |
INTERVAL |
Maximum time (measured in intervals) that Vertica holds a lock. |
HOLD_COUNT |
INTEGER |
Total number of times the lock was granted in the given mode. |
AVG_WAIT_TIME |
INTERVAL |
Average time (measured in intervals) that Vertica waits on the lock. |
MAX_WAIT_TIME |
INTERVAL |
Maximum time (measured in intervals) that Vertica waits on a lock. |
WAIT_COUNT |
INTEGER |
Total number of times lock was unavailable at the time it was first requested. |
Privileges
Non-superuser: No explicit privileges required. You only see records for tables that you have privileges to view.