EXCPVR Option
Use the EXCPVR option instead of the default EXCP option to eliminate any address translation of channel programs by the z/OS I/O supervisor (IOS) each time the channel program supervisor call is invoked.
With EXCPVR, the data areas involved in the I/O operation and the area containing the channel program are page‑fixed. Therefore, address translation for the Channel Control Words (CCWs) that make up the channel programs is done only once, during TDP initialization.