1. Database Reference
  2. Dynamic Performance Views
  3. Dynamic Performance (V$) Views: V$IM_COLUMN_LEVEL to V$RULE_SET_AGGREGATE_STATS
  4. V$IOSTAT_FUNCTION_DETAIL

8.20 V$IOSTAT_FUNCTION_DETAIL

V$IOSTAT_FUNCTION_DETAIL displays disk I/O statistics for database functions (such as the LGWR and DBWR), broken down by file type.

Column Datatype Description

FUNCTION_ID

NUMBER

Function ID

FUNCTION_NAME

VARCHAR2(18)

Function name:

  • RMAN

  • DBWR

  • LGWR

  • ARCH

  • XDB

  • Streams AQ

  • Data Pump

  • Recovery

  • Buffer Cache Reads

  • Direct Reads

  • Direct Writes

  • Smart Scan

  • Archive Manager

  • Others

FILETYPE_ID

NUMBER

File type ID

FILETYPE_NAME

VARCHAR2(28)

File type name:

  • Control File

  • Data File

  • Log File

  • Archive Log

  • Temp File

  • Data File Backup

  • Data File Incremental Backup

  • Archive Log Backup

  • Data File Copy

  • Flashback Log

  • Data Pump Dump File

  • Other

SMALL_READ_MEGABYTES

NUMBER

Number of megabytes read via single block read requests

SMALL_WRITE_MEGABYTES

NUMBER

Number of megabytes written via single block write requests

LARGE_READ_MEGABYTES

NUMBER

Number of megabytes read via multiblock read requests

LARGE_WRITE_MEGABYTES

NUMBER

Number of megabytes written via multiblock write requests

SMALL_READ_REQS

NUMBER

Number of single block read requests

SMALL_WRITE_REQS

NUMBER

Number of single block write requests

LARGE_READ_REQS

NUMBER

Number of multiblock read requests

LARGE_WRITE_REQS

NUMBER

Number of multiblock write requests

NUMBER_OF_WAITS

NUMBER

Number of synchronous I/O waits by functionality

WAIT_TIME

NUMBER

Total synchronous I/O wait time (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