V$KERNEL_IO_OUTLIER

V$KERNEL_IO_OUTLIER contains entries corresponding to I/Os that have taken a long time (more than 500 ms) to complete.

Use this view to see the individual kernel components of I/Os for which there are any occasional delays in serving disk I/O requests by the storage subsystem.

Note: Although this view exists on all platforms in Oracle Database 12c, it is only populated on the Solaris platform.

Column Datatype Description
TIMESTAMP NUMBER Number of seconds elapsed since 00:00 UTC, January 1, 1970
IO_SIZE NUMBER Size of the I/O, in KB.
IO_OFFSET NUMBER Offset into the device of the I/O
DEVICE_NAME VARCHAR2(513) Name of the device to which the I/O was targeted
PROCESS_NAME VARCHAR2(64) Name of the process that issued the I/O
TOTAL_LATENCY NUMBER Total time the I/O spent in the kernel (in milliseconds)
SETUP_LATENCY NUMBER Time spent during initial I/O setup before sending to SCSI target device driver (in milliseconds)
QUEUE_TO_HBA_LATENCY NUMBER Time spent in the SCSI target device driver before being sent to the Host Bus Adaptor (in milliseconds)
TRANSFER_LATENCY NUMBER Time spent in the Host Bus Adaptor and physically transferring the I/O to the storage device (in milliseconds)
CLEANUP_LATENCY NUMBER Time spent freeing resources used by the completed I/O (in milliseconds)
PID NUMBER Process ID that issued the I/O
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: