mp_max_dv Subroutine

      SUBROUTINE mp_max_dv(msg, gid)
      !! Finds the element-wise maximum of a vector with the result left on
      !! all processes.
      !! @note see mp_max_d

         REAL(kind=real_8), CONTIGUOUS, INTENT(INOUT)     :: msg(:)
         !! Find maximum among these data (input) and maximum (output)
         TYPE(mp_comm_type), INTENT(IN)                      :: gid

         CHARACTER(LEN=*), PARAMETER :: routineN = 'mp_max_dv'

         INTEGER                                  :: handle, ierr, msglen

         ierr = 0
         CALL timeset(routineN, handle)

         msglen = SIZE(msg)
#if defined(__parallel)
         CALL mpi_allreduce(MPI_IN_PLACE, msg, msglen, MPI_DOUBLE_PRECISION, MPI_MAX, gid%handle, ierr)
         IF (ierr /= 0) CALL mp_stop(ierr, "mpi_allreduce @ "//routineN)
         CALL add_perf(perf_id=3, msg_size=msglen*real_8_size)
#else
         MARK_USED(gid)
#endif
         CALL timestop(handle)
      END SUBROUTINE mp_max_dv