V$EVENT_HISTOGRAM_MICRO
V$EVENT_HISTOGRAM_MICRO displays a histogram of the number of waits, the maximum wait, and total wait time on an event basis, in microseconds. The histogram has buckets of time intervals from < 1 us, < 2 us, < 4 us, < 8 us, … < 231 us, < 232 us, and >= 232 us.
The histogram will not be filled unless the TIMED_STATISTICS initialization parameter is set to true.
| Column | Datatype | Description |
|---|---|---|
EVENT# |
NUMBER |
Event number |
EVENT |
VARCHAR2(64) |
Name of the event |
WAIT_TIME_FORMAT |
VARCHAR2(30) |
A human readable time string which is converted from WAIT_TIME_MICRO. When WAIT_TIME_MICRO < 1 millisecond, WAIT_TIME_FORMAT is shown in microseconds. When WAIT_TIME_MICRO < 1 second, WAIT_TIME_FORMAT is shown in milliseconds. When WAIT_TIME_MICRO < 1 minute, WAIT_TIME_FORMAT is shown in seconds. When WAIT_TIME_MICRO > 1 minute, WAIT_TIME_FORMAT is shown in minutes and seconds. |
WAIT_TIME_MICRO |
NUMBER |
Amount of time the bucket represents (in microseconds). If the duration = num, then this column represents waits of duration < num that are not included in any smaller bucket. |
WAIT_COUNT |
NUMBER |
Number of waits of the duration belonging to the bucket of the histogram |
LAST_UPDATE_TIME |
VARCHAR2(64) |
Indicates the last time the bucket was updated (the ending timestamp of the last wait falling into the bucket’s duration) |
CON_ID |
NUMBER |
The ID of the container to which the data pertains. Possible values include:
|