Note
This view is introduced since OceanBase Database V4.2.2.
Purpose
The oceanbase.DBA_WR_SYSTEM_EVENT view displays the persisted tenant-level wait events of the current tenant.
Columns
Column |
Type |
Nullable? |
Description |
|---|---|---|---|
| SNAP_ID | bigint(20) | NO | The ID of the snapshot. |
| SVR_IP | varchar(46) | NO | The IP address of the OBServer node. |
| SVR_PORT | bigint(20) | NO | The port number of the OBServer node. |
| EVENT_ID | bigint(20) | NO | The ID of the wait event. |
| EVENT_NAME | varchar(64) | YES | The name of the wait event. |
| WAIT_CLASS_ID | bigint(20) | YES | The ID of the class to which the wait event belongs. |
| WAIT_CLASS | varchar(64) | YES | The name of the class to which the wait event belongs. |
| TOTAL_WAITS | bigint(20) | YES | The total number of waits for the event. |
| TOTAL_TIMEOUTS | bigint(20) | YES | The total number of timeouts for the event. |
| TIME_WAITED_MICRO | bigint(20) | YES | The total wait time for the event. |
The following table lists the names of wait event classes in the WAIT_CLASS column, and the corresponding wait event IDs.
Event class |
Event ID |
Description |
|---|---|---|
| OTHER | 100 | A wait event that does not belong to any other classes. |
| APPLICATION | 101 | A wait event caused by the client code. |
| CONFIGURATION | 102 | A wait event caused by insufficient resources configured for the database or instance. |
| ADMINISTRATIVE | 103 | A wait event caused by a command entered by the database administrator (DBA). |
| CONCURRENCY | 104 | A wait event of waiting for internal resources of the database. |
| COMMIT | 105 | A wait event related to log commitment. |
| IDLE | 106 | A task execution wait event when the session is inactive. |
| NETWORK | 107 | A wait event related to network communication. |
| USER_IO | 108 | A user I/O wait event. |
| SYSTEM_IO | 109 | A wait event of waiting for background process I/O resources. |
| CLUSTER | 111 | A wait event 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