Note
- For OceanBase Database V4.3.x, this view is introduced in V4.3.5.
- For OceanBase Database V4.2.x, this view is introduced in V4.2.2.
Purpose
The DBA_WR_SYSTEM_EVENT view displays the tenant-level waiting events that have been persisted in this tenant.
Columns
| Column | Type | Nullable? | Description |
|---|---|---|---|
| SNAP_ID | bigint(20) | NO | Snapshot ID |
| SVR_IP | varchar(46) | NO | Node IP |
| SVR_PORT | bigint(20) | NO | Node port |
| EVENT_ID | bigint(20) | NO | Waiting event ID |
| EVENT_NAME | varchar(64) | YES | Waiting event name |
| WAIT_CLASS_ID | bigint(20) | YES | ID of the waiting event category |
| WAIT_CLASS | varchar(64) | YES | Name of the waiting event category |
| TOTAL_WAITS | bigint(20) | YES | Total number of times the waiting event has occurred |
| TOTAL_TIMEOUTS | bigint(20) | YES | Total number of times the waiting event has timed out |
| TIME_WAITED_MICRO | bigint(20) | YES | Total waiting time of the waiting event |
The following table describes the values in the WAIT_CLASS column of the view.
| Waiting event category | Waiting event ID | Description |
|---|---|---|
| OTHER | 100 | Waiting events that do not belong to other categories |
| APPLICATION | 101 | Waiting events caused by client-side code |
| CONFIGURATION | 102 | Waiting events caused by insufficient configurations of database or instance resources |
| ADMINISTRATIVE | 103 | Waiting events caused by commands entered by database administrators |
| CONCURRENCY | 104 | Waiting events for waiting for internal database resources |
| COMMIT | 105 | Waiting events related to log commit |
| IDLE | 106 | Waiting events for waiting for tasks when a session is inactive |
| NETWORK | 107 | Waiting events related to network communication |
| USER_IO | 108 | Waiting events for waiting for user I/O |
| SYSTEM_IO | 109 | Waiting events for waiting for I/O by background processes |
| CLUSTER | 111 | Waiting events related to clusters |
Sample query
obclient [oceanbase]> SELECT * FROM oceanbase.DBA_WR_SYSTEM_EVENT LIMIT 10;
The query result is as follows:
+---------+----------------+----------+----------+-----------------------------------+---------------+-------------+-------------+----------------+-------------------+
| SNAP_ID | SVR_IP | SVR_PORT | EVENT_ID | EVENT_NAME | WAIT_CLASS_ID | WAIT_CLASS | TOTAL_WAITS | TOTAL_TIMEOUTS | TIME_WAITED_MICRO |
+---------+----------------+----------+----------+-----------------------------------+---------------+-------------+-------------+----------------+-------------------+
| 1 | 172.xx.xxx.xxx | 2882 | 2 | latch: default spin rwlock wait | 104 | CONCURRENCY | 9 | 0 | 2514 |
| 1 | 172.xx.xxx.xxx | 2882 | 3 | latch: default mutex wait | 104 | CONCURRENCY | 318 | 0 | 14740 |
| 1 | 172.xx.xxx.xxx | 2882 | 8 | latch: trans ctx latch wait | 104 | CONCURRENCY | 15 | 0 | 15244 |
| 1 | 172.xx.xxx.xxx | 2882 | 40 | latch: config lock wait | 104 | CONCURRENCY | 14 | 0 | 207794 |
| 1 | 172.xx.xxx.xxx | 2882 | 99 | latch: tablet bucket lock wait | 104 | CONCURRENCY | 1 | 0 | 1334 |
| 1 | 172.xx.xxx.xxx | 2882 | 258 | latch: palf handle impl lock wait | 104 | CONCURRENCY | 3 | 0 | 186 |
| 1 | 172.xx.xxx.xxx | 2882 | 283 | latch: ls meta lock wait | 104 | CONCURRENCY | 26 | 0 | 3568 |
| 1 | 172.xx.xxx.xxx | 2882 | 10001 | db file data read | 108 | USER_IO | 2 | 0 | 3946 |
| 1 | 172.xx.xxx.xxx | 2882 | 11001 | db file compact read | 109 | SYSTEM_IO | 1545 | 0 | 816400 |
| 1 | 172.xx.xxx.xxx | 2882 | 11002 | db file compact write | 109 | SYSTEM_IO | 10292 | 0 | 1420220 |
+---------+----------------+----------+----------+-----------------------------------+---------------+-------------+-------------+----------------+-------------------+
10 rows in set