11 Communication setup

11.1 Module cpl_comm_mod - Define MPI communication groups and model ID's (Source File: cpl_comm_mod.F90)

Sets up communicator groups and component ID's.

A component ID (CID) is an integer identifying each component in the coupled system. Valid values are 1 to the total number of models (including the Coupler). Declaring an integer for each model is a requirement of using MCT.

Use MPH to define the communicator groups and component ID's.

This module also declares and defines handy data wrt number of pe's, PID's, CID's relative to world and component communicator groups.

REVISION HISTORY:

       2001-Aug-20 - B. Kauffman - new naming convention
       2001-Mar-20 - T. Craig, B. Kauffman, R. Jacob - first prototype

INTERFACE:

 
 module cpl_comm_mod

USES:

 
   use cpl_kind_mod   ! kinds
   use shr_sys_mod    ! system calls
   use shr_mpi_mod    ! mpi layer
 
   implicit none
 
   private ! except

PUBLIC TYPES:

 
   ! none

PUBLIC MEMBER FUNCTIONS:

 
    public :: cpl_comm_init

PUBLIC DATA MEMBERS:

 
    integer(IN),public :: cpl_comm_wrld         ! = MPI_COMM_WORLD, global comm grp
    integer(IN),public :: cpl_comm_wrld_npe     ! number of pe's in MPI_COMM_WORLD
    integer(IN),public :: cpl_comm_wrld_pid     ! this comp pid in MPI_COMM_WORLD
 
    integer(IN),public :: cpl_comm_comp         ! this comp communicator group
    integer(IN),public :: cpl_comm_comp_npe     ! number of pe's in comp comm group
    integer(IN),public :: cpl_comm_comp_pid     ! this comp's pid in comp comm group
 
    integer(IN),public :: cpl_comm_mph_cid      ! MPH component ID, this component
    integer(IN),public :: cpl_comm_mph_cid_atm  ! MPH component ID, atm
    integer(IN),public :: cpl_comm_mph_cid_ice  ! MPH component ID, ice
    integer(IN),public :: cpl_comm_mph_cid_lnd  ! MPH component ID, lnd
    integer(IN),public :: cpl_comm_mph_cid_ocn  ! MPH component ID, ocn
    integer(IN),public :: cpl_comm_mph_cid_cpl  ! MPH component ID, cpl
 
    integer(IN),public :: cpl_comm_wrld_pe0     ! comm world pe0, this component
    integer(IN),public :: cpl_comm_wrld_pe0_atm ! comm world pe0, atm
    integer(IN),public :: cpl_comm_wrld_pe0_ice ! comm world pe0, ice
    integer(IN),public :: cpl_comm_wrld_pe0_lnd ! comm world pe0, lnd
    integer(IN),public :: cpl_comm_wrld_pe0_ocn ! comm world pe0, ocn
    integer(IN),public :: cpl_comm_wrld_pe0_cpl ! comm world pe0, cpl

11.1.1 cpl_comm_init - initialize the coupling/mpi environment.

This routine calls MPI_init for the model with name name and returns an MPI_Communicator comm for use in the calling model. This also sets component ids, and processor ranks relative to world and component communicator groups.

REMARKS:

      Use cpl_interface_init which calls this routine.

REVISION HISTORY:

       2001-Mar-20 - T. Craig, B. Kauffman, R. Jacob -- first prototype
       2001-Dec-10 - R. Jacob -- switch arguments in cpl_mct_world_init to
                     to match new version

INTERFACE:

 
 subroutine cpl_comm_init(name,comm)

USES:

 
    use cpl_fields_mod      ! contains valid component name strings
    use mph_module,only : mph_components
    use mph_module,only : mph_global_proc_id
    use mph_module,only : mph_local_proc_id
    use mph_module,only : mph_total_components
    use mph_module,only : mph_comp_id
    use mph_module,only : mph_local_totprocs
    use mph_module,only : mph_global_totprocs
    use mph_module,only : mph_global_id
    use mph_module,only : mph_comp_name
    use mph_module,only : mph_global_world
    use m_MCTWorld    ,only : cpl_mct_world_init   => init
 
    implicit none

INPUT/OUTPUT PARAMETERS:

 
    character(*),intent(in)  :: name ! name of component name
    integer(IN) ,intent(out) :: comm ! communicator group for component