V$SESSION_EVENT
V$SESSION_EVENT显示有关会话等待事件的信息。请注意,在不支持快速计时机制的平台上,TIME_WAITED和AVERAGE_WAIT列将包含零值。如果您正在其中一个平台上运行,并希望此列反映真实的等待时间,则必须将参数TIMED_STATISTICS设置为true; 这样做会对系统性能产生很小的负面影响。
Column |
Datatype |
Description |
SID |
NUMBER |
ID of the session |
EVENT |
VARCHAR2(64) |
Name of the wait event |
TOTAL_WAITS |
NUMBER |
Total number of waits for the event by the session |
TOTAL_TIMEOUTS |
NUMBER |
Total number of timeouts for the event by the session |
TIME_WAITED |
NUMBER |
Total amount of time waited for the event by the session (in hundredths of a second) |
AVERAGE_WAIT |
NUMBER |
Average amount of time waited for the event by the session (in hundredths of a second) |
MAX_WAIT |
NUMBER |
Maximum time waited for the event by the session (in hundredths of a second) |
TIME_WAITED_MICRO |
NUMBER |
Total amount of time waited for the event by the session (in microseconds) |
EVENT_ID |
NUMBER |
Identifier of the wait event |
WAIT_CLASS_ID |
NUMBER |
Identifier of the class of the wait event |
WAIT_CLASS# |
NUMBER |
Number of the class of the wait event |
WAIT_CLASS |
VARCHAR2(64) |
Name of the class of the wait event |
CON_ID |
NUMBER |
The ID of the container to which the data pertains. Possible values include: 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs. n: Where n is the applicable container ID for the rows containing data |
列的解释
MAX_WAIT:等待事件最长的时间(百分之一秒)