V$MUTEX_SLEEP_HISTORY
V$MUTEX_SLEEP_HISTORY displays time-series data.
Each row in this view is for a specific time, mutex type, location, requesting session and blocking session combination. That is, it shows data related to a specific session (requesting session) that slept while requesting a specific mutex type and location, because it was being held by a specific blocking session. The data in this view is contained within a circular buffer, with the most recent sleeps shown.
| Column | Datatype | Description |
|---|---|---|
MUTEX_IDENTIFIER |
NUMBER |
Mutex ID |
SLEEP_TIMESTAMP |
TIMESTAMP(6) |
The last date/time this MUTEX_TYPE and LOCATION was slept for by the REQUESTING_SESSION, while being held by the BLOCKING_SESSION. |
MUTEX_TYPE |
VARCHAR2(32) |
Type of action/object the mutex protects |
GETS |
NUMBER |
The total number of gets since the mutex was created and up until the time of the wait (and from all sessions past and present) |
SLEEPS |
NUMBER |
The number of times the requester had to sleep before obtaining the mutex |
REQUESTING_SESSION |
NUMBER |
The SID of a session requesting the mutex |
BLOCKING_SESSION |
NUMBER |
The SID of a session holding the mutex |
LOCATION |
VARCHAR2(40) |
The code location where the waiter slept for the mutex |
MUTEX_VALUE |
RAW(4 | 8) |
If the mutex is held in exclusive (X) mode, this column shows the SID of the blocking session, else it shows the number of sessions referencing the mutex in S mode. |
P1 |
NUMBER |
Reserved for internal use |
P1RAW |
RAW(4 | 8) |
Reserved for internal use |
P2 |
NUMBER |
Reserved for internal use |
P3 |
NUMBER |
Reserved for internal use |
P4 |
NUMBER |
Reserved for internal use |
P5 |
VARCHAR2(64) |
Reserved for internal use |
CON_ID |
NUMBER |
The ID of the container to which the data pertains. Possible values include:
|