Note
This view is available starting with V4.2.2.
Overview
The CDB_WR_SYSTEM_EVENT view displays persistent tenant-level wait event information for all tenants.
Columns
Field |
Type |
Nullable |
Description |
|---|---|---|---|
| TENANT_ID | bigint(20) | NO | Tenant ID |
| CLUSTER_ID | bigint(20) | NO | Cluster ID |
| SNAP_ID | bigint(20) | NO | Snapshot ID |
| SVR_IP | varchar(46) | NO | Node IP |
| SVR_PORT | bigint(20) | NO | Node Port Number |
| EVENT_ID | bigint(20) | NO | Wait for Event ID |
| EVENT_NAME | varchar(64) | YES | Wait for Event Name |
| WAIT_CLASS_ID | bigint(20) | YES | ID of the wait-for-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 Timeout Count of Waiting Events |
| TIME_WAITED_MICRO | bigint(20) | YES | Total Waiting Time for Events |
The values in the WAIT_CLASS column of the view contain the type names and corresponding event IDs of the wait events. The following table describes these.
Type of the event to be waited for |
Event Number |
Description |
|---|---|---|
| OTHER | 100 | Waiting Events Not Belonging to Other Types |
| APPLICATION | 101 | Wait Events Caused by Client Code |
| CONFIGURATION | 102 | Waiting Events Caused by Insufficient Database or Instance Resource Configuration |
| ADMINISTRATIVE | 103 | Wait events caused by database administrators entering commands |
| CONCURRENCY | 104 | Wait events for internal database resources |
| COMMIT | 105 | Waiting Events Related to Log Commit |
| IDLE | 106 | The session is in an inactive state, waiting for the task's wait event. |
| NETWORK | 107 | Network Communication Related Waiting Events |
| USER_IO | 108 | I/O Waiting Events |
| SYSTEM_IO | 109 | I/O Waiting Event for Background Processes |
| CLUSTER | 111 | Cluster-related wait events |
Sample query
Query the persistent tenant-level wait event information of tenant 1004 and display the first 10 records.
obclient [oceanbase]> SELECT * FROM oceanbase.CDB_WR_SYSTEM_EVENT WHERE TENANT_ID= 1004 LIMIT 10;
The query result is as follows:
+-----------+------------+---------+----------------+----------+----------+----------------------------------------------------+---------------+-------------+-------------+----------------+-------------------+
| TENANT_ID | CLUSTER_ID | SNAP_ID | SVR_IP | SVR_PORT | EVENT_ID | EVENT_NAME | WAIT_CLASS_ID | WAIT_CLASS | TOTAL_WAITS | TOTAL_TIMEOUTS | TIME_WAITED_MICRO |
+-----------+------------+---------+----------------+----------+----------+----------------------------------------------------+---------------+-------------+-------------+----------------+-------------------+
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 2 | latch: default spin rwlock wait | 104 | CONCURRENCY | 8 | 0 | 1339 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 3 | latch: default mutex wait | 104 | CONCURRENCY | 349 | 0 | 16079 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 8 | latch: trans ctx latch wait | 104 | CONCURRENCY | 6 | 0 | 15328 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 40 | latch: config lock wait | 104 | CONCURRENCY | 6 | 0 | 159968 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 99 | latch: tablet bucket lock wait | 104 | CONCURRENCY | 1 | 0 | 1177 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 197 | latch: weak read service cluster service lock wait | 104 | CONCURRENCY | 1 | 0 | 1 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 217 | latch: FIFO allocator lock wait | 104 | CONCURRENCY | 1 | 0 | 29 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 258 | latch: palf handle impl lock wait | 104 | CONCURRENCY | 4 | 0 | 185 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 278 | latch: max apply scn lock wait | 104 | CONCURRENCY | 1 | 0 | 21 |
| 1004 | 10001 | 1 | 172.xx.xxx.xxx | 2882 | 283 | latch: ls meta lock wait | 104 | CONCURRENCY | 34 | 0 | 4998 |
+-----------+------------+---------+----------------+----------+----------+----------------------------------------------------+---------------+-------------+-------------+----------------+-------------------+
10 rows in set