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:
  | 
FILETYPE_ID | 
NUMBER | 
File type ID | 
FILETYPE_NAME | 
VARCHAR2(28) | 
File type name:
  | 
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) |