High Performance Input/Output interface
The High Performance Input/Output (HP Input/Output or HPIO) interface reduces CPU time and usage while IMS HP Image Copy generates image copies or recovers a database.
You can use HP Input/Output to read the database data set to generate image copies and to write the data set to recover from regular image copy processing.
The following table shows the types of data sets that are supported by the
HP
Input/Output interface.
| Data set type | I/O method | Description |
|---|---|---|
| OSAM (read and write processing) | EXCP | Used for batch and concurrent image copy processing. |
| VSAM ESDS (read processing) | EXCP or Media Manager depending on the database type | Used for batch and concurrent image copy processing. Media Manager does not support the overflow data set of HISAM and secondary index databases. |
| VSAM KSDS (read processing) | VSAM I/O | When the data set is a VSAM KSDS, VSAM I/O is always used. |
If access method or copy criteria are not compatible with HP Input/Output, IMS HP Image Copy uses the normal access method.
You can enable the HP Input/Output interface by specifying HPIO=Y on the PARM parameter of the EXEC statement in DFSUDMP0 JCL.