DBA_HIST_IOSTAT_FUNCTION

DBA_HIST_IOSTAT_FUNCTION displays historical I/O statistics by function. This view contains snapshots of V$IOSTAT_FUNCTION.

Column	Datatype	NULL	Description
`SNAP_ID`	`NUMBER`	`NOT NULL`	Unique snapshot ID
`DBID`	`NUMBER`	`NOT NULL`	Database ID for the snapshot
`INSTANCE_NUMBER`	`NUMBER`	`NOT NULL`	Instance number for the snapshot
`FUNCTION_ID`	`NUMBER`	`NOT NULL`	Function ID
`FUNCTION_NAME`	`VARCHAR2(18)`	`NOT NULL`	Function name
`SMALL_READ_MEGABYTES`	`NUMBER`	`NOT NULL`	Number of single block megabytes read
`SMALL_WRITE_MEGABYTES`	`NUMBER`	`NOT NULL`	Number of single block megabytes written
`LARGE_READ_MEGABYTES`	`NUMBER`	`NOT NULL`	Number of multiblock megabytes read
`LARGE_WRITE_MEGABYTES`	`NUMBER`	`NOT NULL`	Number of multiblock megabytes written
`SMALL_READ_REQS`	`NUMBER`	`NOT NULL`	Number of single block read requests
`SMALL_WRITE_REQS`	`NUMBER`	`NOT NULL`	Number of single block write requests
`LARGE_READ_REQS`	`NUMBER`	`NOT NULL`	Number of multiblock read requests
`LARGE_WRITE_REQS`	`NUMBER`	`NOT NULL`	Number of multiblock write requests
`NUMBER_OF_WAITS`	`NUMBER`	`NOT NULL`	Number of I/O waits by functionality
`WAIT_TIME`	`NUMBER`	`NOT NULL`	Total wait time (in milliseconds)