Note
- For V4.3.x, this view was introduced in V4.3.5.
- For V4.2.x, this view was introduced in V4.2.2.
Purpose
The DBA_WR_SYSTEM_EVENT view displays the tenant-level persistent wait events of the current 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 | Wait event ID |
| EVENT_NAME | varchar(64) | YES | Wait event name |
| WAIT_CLASS_ID | bigint(20) | YES | ID of the wait event category |
| WAIT_CLASS | varchar(64) | YES | Name of the wait event category |
| TOTAL_WAITS | bigint(20) | YES | Total number of wait events |
| TOTAL_TIMEOUTS | bigint(20) | YES | Total number of timeouts |
| TIME_WAITED_MICRO | bigint(20) | YES | Total wait time |
The following table describes the wait event categories and their corresponding wait event IDs in the WAIT_CLASS column of the view.
| Wait event category | Wait event ID | Description |
|---|---|---|
| OTHER | 100 | Wait events that do not belong to other categories |
| APPLICATION | 101 | Wait events caused by client-side code |
| CONFIGURATION | 102 | Wait events caused by insufficient database or instance resource configurations |
| ADMINISTRATIVE | 103 | Wait events caused by user waits due to database administrator commands |
| CONCURRENCY | 104 | Wait events caused by waiting for internal database resources |
| COMMIT | 105 | Wait events related to log commit |
| IDLE | 106 | Wait events caused by idle sessions waiting for tasks |
| NETWORK | 107 | Wait events related to network communication |
| USER_IO | 108 | Wait events caused by waiting for user I/O |
| SYSTEM_IO | 109 | Wait events caused by waiting for I/O by background processes |
| CLUSTER | 111 | Wait 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 | 7 | 0 | 113693 |
| 1 | 172.xx.xxx.xxx | 2882 | 3 | latch: default mutex wait | 104 | CONCURRENCY | 517 | 0 | 29687 |
| 1 | 172.xx.xxx.xxx | 2882 | 8 | latch: trans ctx latch wait | 104 | CONCURRENCY | 84 | 0 | 68001 |
| 1 | 172.xx.xxx.xxx | 2882 | 33 | latch: ls latch wait | 104 | CONCURRENCY | 2 | 0 | 9829 |
| 1 | 172.xx.xxx.xxx | 2882 | 40 | latch: config lock wait | 104 | CONCURRENCY | 20 | 0 | 358460 |
| 1 | 172.xx.xxx.xxx | 2882 | 47 | latch: rs bootstrap lock wait | 104 | CONCURRENCY | 1 | 0 | 29706546 |
| 1 | 172.xx.xxx.xxx | 2882 | 55 | latch: unit manager lock wait | 104 | CONCURRENCY | 2 | 0 | 2965 |
| 1 | 172.xx.xxx.xxx | 2882 | 92 | latch: block manager lock wait | 104 | CONCURRENCY | 1 | 0 | 5 |
| 1 | 172.xx.xxx.xxx | 2882 | 99 | latch: tablet bucket lock wait | 104 | CONCURRENCY | 3 | 0 | 2684 |
| 1 | 172.xx.xxx.xxx | 2882 | 202 | latch: zone merge manager write lock wait | 104 | CONCURRENCY | 1 | 0 | 554 |
+---------+----------------+----------+----------+-------------------------------------------+---------------+-------------+-------------+----------------+-------------------+
10 rows in set