Datafiles Page
Use the Datafiles Page, Tablespaces Page, and Segment Page to view the logical and physical structures that have the highest rates of I/O activity in the database.
Datafiles are the physical structures that contain the data that makes up an Oracle database.
Data in this drilldown is derived from V$IOSTAT_FILE.
To open the Datafiles page
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Select the Spotlight on Oracle RAC connection in the Spotlight Browser.
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Click I/O | Datafiles.
Select a Tablespace
Select from the Tablespace list to view the I/O activity for the datafiles within the specified tablespace. Any given database file can belong to only one tablespace.
Charts on the Datafiles Page
| Chart | Description |
|---|---|
| Throughput - requests (Top 20) |
Throughput—Requests shows the rate of I/O requests for the top 20 datafiles (by read time) in the tablespace. The rate is measured by the number of physical I/O requests per second. Values that are consistently high over the displayed period are those most likely to contribute to performance bottlenecks. |
| Latency (Top 20) |
For the top 20 datafiles (by read time), Latency shows the average time (in milliseconds) taken to process a physical I/O request on each datafile. Values that are consistently high over the displayed period are those most likely to contribute to performance bottlenecks. |
Datafiles grid
The Datafiles table shows information about I/O activity on the datafiles in the selected tablespace.
By default, the grid is ordered by the Read latency (ms) column to show which datafiles have the highest latency. High values in the Read latency (ms) column may indicate datafiles are on disks with potential bottlenecks. Datafiles could be placed on a different physical disk to balance the I/O for the tablespace.
Note: Not all columns are visible by default. Use the Column Organizer to view hidden columns. Show, Hide & Order Columns
| Column | Description |
|---|---|
|
File name |
The name of the datafile. |
|
Tablespace name |
The name of the tablespace that contains it. |
|
Read Latency (ms) |
The average time taken to perform a read request on the datafile. Note: A zero value in this column indicates a datafile that is currently idle. |
|
Requests/s |
The rate of read requests on the datafile. |
|
Read Requests |
The total number of read requests on the datafile since instance startup. |
|
Write Requests |
The total number of write requests on the datafile since instance startup. |
|
Read Time (s) |
The total time taken to perform read requests on the datafile since instance startup. |
|
Write Time (s) |
The total time taken to perform write requests on the datafile since instance startup. |
|
Read Megabytes |
The number of megabytes of data read from the datafile since instance startup. |
|
Write Megabytes |
The number of megabytes of data written to the datafile since instance startup. |
|
Write Latency (ms) |
The average time taken to perform a write request on the datafile. |