V$LGWRIO_OUTLIER

V$LGWRIO_OUTLIER contains entries corresponding to Log Writer (LGWR) process I/Os that have taken a long time (more than 500 ms) to complete. Use this view to see if there any occasional delays in serving disk I/O requests by the storage subsystem.

Column Datatype Description

FUNCTION_NAME

VARCHAR2(18)

I/O function name of the delayed I/O

IO_SIZE

NUMBER

Size of the I/O in bytes

WAIT_EVENT

VARCHAR2(64)

Wait event name that was used to track the I/O

FILE_NAME

VARCHAR2(513)

Name of the file to which the I/O was targeted

IO_LATENCY

NUMBER

Time taken to complete the I/O (in milliseconds)

DISK1_NAME

VARCHAR2(255)

For Oracle ASM, the name of the first disk to which the I/O was issued

DISK1_LATENCY

NUMBER

Latency seen on the first disk (in milliseconds)

DISK2_NAME

VARCHAR2(255)

For Oracle ASM, the name of the second disk to which the I/O was issued

DISK2_LATENCY

NUMBER

Latency seen on the second disk (in milliseconds)

DISK3_NAME

VARCHAR2(255)

For Oracle ASM, the name of the third disk to which the I/O was issued

DISK3_LATENCY

NUMBER

Latency seen on the third disk (in milliseconds)

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.

  • 1: This value is used for rows containing data that pertain to only the root

  • n: Where n is the applicable container ID for the rows containing data

See Also: