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(30) |
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) |