Initialisation

All processes of the component model initialise the coupling and, if required, retrieve a local communicator for the component model internal parallelisation.

• USE mod_prism_proto

  Module to be used by the component models.

• CALL prism_init_comp_proto (compid, model_name, ierror)
  • compid [INTEGER; OUT]: component model ID
  • model_name [CHARACTER*6; IN]: name of calling model (as in namcouple)
  • ierror [INTEGER; OUT]: returned error code.

  Routine called by all component model processes, which initialises the coupling.²

• CALL prism_get_localcomm_proto (local_comm, ierror )
  • local_comm [INTEGER; OUT]: value of local communicator
  • ierror [INTEGER; OUT]: returned error code.

  If needed, routine called by all model processes to get the value of a local communicator to be used by the model for its internal parallelisation (CLIM-MPI1 communication technique only).

  With CLIM-MPI1, all component models started in a pseudo-MPMD mode share automatically the same MPI_COMM_WORLD communicator. Another communicator has to be used for the internal parallelisation of each model. OASIS3 creates this model local communicator based on the name of the calling model; its value is returned as the first argument of prism_get_localcomm_proto routine.

  With CLIM-MPI2, OASIS3 executable spawns the component model executables at the beginning of the run; the components keep their internal parallelisation context unchanged with respect to their standalone mode. In this case, calling the prism_get_localcomm_proto routine is useless but if called, the communicator MPI_COMM_WORLD will be returned as local communicator.

Footnotes

... coupling.²

The model may call MPI_Init explicitly, but if so, has to call it before calling prism_init_comp_proto; in this case, the model also has to call MPI_Finalize explicitly, but only after calling prism_terminate_proto.