Note
This view is introduced since OceanBase Database V4.2.2.
Purpose
The oceanbase.CDB_WR_EVENT_NAME view displays the names of persisted tenant-level wait events in all tenants.
Columns
| Column | Type | Nullable? | Description |
|---|---|---|---|
| TENANT_ID | bigint(20) | No | The ID of the tenant. |
| CLUSTER_ID | bigint(20) | No | The ID of the cluster. |
| EVENT_ID | bigint(20) | No | The ID of the wait event. |
| EVENT_NAME | varchar(64) | Yes | The name of the wait event. |
| PARAMETER1 | varchar(64) | Yes | The name of the first parameter of the wait event. |
| PARAMETER2 | varchar(64) | Yes | The name of the second parameter of the wait event. |
| PARAMETER3 | varchar(64) | Yes | The name of the third parameter of the wait event. |
| WAIT_CLASS_ID | bigint(20) | Yes | The ID of the wait event class. |
| WAIT_CLASS | varchar(64) | Yes | The name of the wait event class. |
The following table describes the class and ID of the wait event in the WAIT_CLASS column of the view.
| Event class | Event ID | Description |
|---|---|---|
| OTHER | 100 | The wait event that does not belong to any other types described in the table. |
| APPLICATION | 101 | The wait event caused by client code. |
| CONFIGURATION | 102 | The wait event caused by insufficient database or instance resources. |
| ADMINISTRATIVE | 103 | The wait event caused by the command entered by the database administrator. |
| CONCURRENCY | 104 | The wait event that waited for internal resources of the database. |
| COMMIT | 105 | The wait event related to log commit. |
| IDLE | 106 | The wait event that waited for the task execution in an idle session. |
| NETWORK | 107 | The wait event related to network communication. |
| USER_IO | 108 | The wait event that waited for user I/O requests. |
| SYSTEM_IO | 109 | The wait event that waited for I/O requests of the background process. |
| CLUSTER | 111 | The wait event related to the cluster. |
Example
obclient [oceanbase]> SELECT * FROM oceanbase.CDB_WR_EVENT_NAME WHERE TENANT_ID= 1004 LIMIT 10;
The query result is as follows:
+-----------+------------+----------+-----------------------------------+------------+------------+------------+---------------+-------------+
| TENANT_ID | CLUSTER_ID | EVENT_ID | EVENT_NAME | PARAMETER1 | PARAMETER2 | PARAMETER3 | WAIT_CLASS_ID | WAIT_CLASS |
+-----------+------------+----------+-----------------------------------+------------+------------+------------+---------------+-------------+
| 1004 | 10001 | 0 | latch: latch wait queue lock wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 1 | latch: default spin lock wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 2 | latch: default spin rwlock wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 3 | latch: default mutex wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 4 | latch: kv cache bucket latch wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 5 | latch: time wheel task latch wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 7 | latch: election latch wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 8 | latch: trans ctx latch wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 14 | latch: clog reconfirm latch wait | address | number | tries | 104 | CONCURRENCY |
| 1004 | 10001 | 17 | latch: clog task latch wait | address | number | tries | 104 | CONCURRENCY |
+-----------+------------+----------+-----------------------------------+------------+------------+------------+---------------+-------------+
10 rows in set