Note
This view is available starting with V1.4.
Purpose
This view displays the wait events of all tenants on all OBServer nodes in the cluster, including the number of occurrences, wait time, timeout count, and other statistics for each type of wait event.
Columns
| Column | Type | Nullable | Description |
|---|---|---|---|
| CON_ID | bigint(20) | NO | The tenant ID. |
| SVR_IP | varchar(46) | NO | The IP address of the server where the information is stored. |
| SVR_PORT | bigint(20) | NO | The port number of the server where the information is stored. |
| EVENT_ID | bigint(20) | NO | The ID of the wait event. |
| EVENT | varchar(64) | NO | The description of the wait event. |
| WAIT_CLASS_ID | bigint(20) | NO | The ID of the class to which the wait event belongs. |
| WAIT_CLASS# | bigint(20) | NO | The index of the class to which the wait event belongs. |
| WAIT_CLASS | varchar(64) | NO | The class to which the wait event belongs. |
| TOTAL_WAITS | bigint(20) | NO | The total number of wait events. |
| TOTAL_TIMEOUTS | bigint(20) | NO | The total number of timeouts. |
| TIME_WAITED | double | NO | The total wait time of the wait event, in 10 ms. |
| AVERAGE_WAIT | double | NO | The average wait time of the wait event, in 10 ms. |
| TIME_WAITED_MICRO | bigint(20) | NO | The total wait time of the wait event, in microseconds. |
Sample query
In the sys tenant, query all wait events of all tenants on all nodes, and display the first 10 records.
obclient [oceanbase]> SELECT * FROM oceanbase.GV$SYSTEM_EVENT LIMIT 10;
The query result is as follows:
+--------+----------------+----------+----------+-------------------------------------+---------------+-------------+---------------+-------------+----------------+-------------+----------------------+-------------------+
| CON_ID | SVR_IP | SVR_PORT | EVENT_ID | EVENT | WAIT_CLASS_ID | WAIT_CLASS# | WAIT_CLASS | TOTAL_WAITS | TOTAL_TIMEOUTS | TIME_WAITED | AVERAGE_WAIT | TIME_WAITED_MICRO |
+--------+----------------+----------+----------+-------------------------------------+---------------+-------------+---------------+-------------+----------------+-------------+----------------------+-------------------+
| 1 | 11.xxx.xxx.xxx | 28825 | 10001 | db file data read | 108 | 8 | USER_IO | 1062255 | 0 | 13525.925 | 0.01273321848332086 | 135259250 |
| 1 | 11.xxx.xxx.xxx | 28825 | 11001 | db file compact read | 109 | 9 | SYSTEM_IO | 1412366 | 0 | 56152.2317 | 0.03975756404501383 | 561522317 |
| 1 | 11.xxx.xxx.xxx | 28825 | 11002 | db file compact write | 109 | 9 | SYSTEM_IO | 311353 | 0 | 17540.5111 | 0.05633641268913419 | 175405111 |
| 1 | 11.xxx.xxx.xxx | 28825 | 11016 | palf read | 109 | 9 | SYSTEM_IO | 914 | 0 | 29.6847 | 0.03247778993435448 | 296847 |
| 1 | 11.xxx.xxx.xxx | 28825 | 11017 | palf write | 109 | 9 | SYSTEM_IO | 9706706 | 0 | 239668.5615 | 0.024691029222477737 | 2396685615 |
| 1 | 11.xxx.xxx.xxx | 28825 | 13000 | sync rpc | 107 | 7 | NETWORK | 908785 | 0 | 53998.3223 | 0.059418148737050015 | 539983223 |
| 1 | 11.xxx.xxx.xxx | 28825 | 13001 | mysql response wait client | 106 | 6 | IDLE | 5324 | 0 | 73.8805 | 0.013876878287002254 | 738805 |
| 1 | 11.xxx.xxx.xxx | 28825 | 13003 | external table wait remote response | 107 | 7 | NETWORK | 1 | 0 | 0.0137 | 0.0137 | 137 |
| 1 | 11.xxx.xxx.xxx | 28825 | 13004 | wait in request queue | 102 | 2 | CONFIGURATION | 6159353 | 0 | 14228.6415 | 0.002310087033491992 | 142286415 |
| 1 | 11.xxx.xxx.xxx | 28825 | 15101 | default condition wait | 104 | 4 | CONCURRENCY | 5743569 | 0 | 219216.8729 | 0.03816736125221095 | 2192168729 |
+--------+----------------+----------+----------+-------------------------------------+---------------+-------------+---------------+-------------+----------------+-------------+----------------------+-------------------+
10 rows in set
References
To query the current or previous wait events of all sessions:
To query all wait events at the session level:
To query the definitions of all wait events of a tenant: V$EVENT_NAME
For more information about wait events, see Common wait events.