DBA_HIST_IOSTAT_DETAIL displays I/O statistics aggregated by combination of file type and function (component). This view contains snapshots of V$IOSTAT_FILE and V$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 |
FILETYPE_ID |
NUMBER |
NOT NULL |
Type of file (for example, log file, data file, and so on) |
FILETYPE_NAME |
VARCHAR2(30) |
NOT NULL |
Name of the file, in the case of a data file or temp file. For all other files, a corresponding string to be displayed (for example, ARCHIVELOG). |
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) |