gtpm3m0b | Multi-Processor Interconnect Facility Reference |
MPIF uses channel-to-channel (CTC) communication links to establish connections between connected TPF complexes. Once these cross-system connections are made, logical connections can be established between MPIF users. Once the logical connection is established, transfer of data and commands across a path between the two MPIF users can be requested.
MPIF provides the typical TPF system control functions, such as error detection and buffer management. It is suitable for TPF system service programs that will be enhanced to schedule their services in one system (the requesting system) and perform their services in another locally-connected system (the server system).
MPIF allows TPF system services to be designed as resident or non-resident functions in that they can perform the service either in the requester's processor or in a locally attached processor. Any MPIF user connected to another user is be able to interact with no awareness of the location of the other user. MPIF resolves the residency question. Any control program service enhanced to be non-resident determines whether the service should be performed in the requester's processor or in a locally, channel attached processor. For the latter condition, the function uses MPIF to transfer the request to the appropriate processor. The TPF system service provides the same view to the requester regardless of whether the processing is performed in this processor or in a locally attached processor. A response to the requester has the same meaning, but the time to execute might be different.