The ABINIT Users Mailing List ( CLOSED )

[Marc Torrent <marc.torrent@cea.fr>]

Eric,


Eric Roman a écrit :
> I also changed xdef_comm.f to return a non-zero constant in case it was
> running in serial.  (This should be unnecessary, due to the way the
> preprocessor is used, but I did it just to clarify things, and for safety
> in case a similar change arises in the future.)


We (of course) had the same idea: return a non-zero constant when 
MPI_COMM_WORLD has to be "undefined" (let's name it "abinit_comm_self").


Eric Roman a écrit :
> I changed the (spaceComm /= 0) tests to (spaceComm /= MPI_COMM_SELF) 
inside
> the reduction routines in xfuncmpi.f.  I'm fairly certain this is the 
correct
> way to do things.


We prefered to replace (spaceComm /= 0) tests by (spaceComm /= 
abinit_comm_self). What do you think about that ?


Regards,

Marc



Eric Roman a écrit :
> Marc
>
> Thanks for confirming, and thanks for your help on this.
>
> I produced a patch last night along these lines.  I've not yet tested it,
> but tell me if you think this is the right way to go.
>
> I changed the (spaceComm /= 0) tests to (spaceComm /= MPI_COMM_SELF) inside
> the reduction routines in xfuncmpi.f.  I'm fairly certain this is the correct
> way to do things.
>
> I also changed xdef_comm.f to return a non-zero constant in case it was
> running in serial.  (This should be unnecessary, due to the way the 
> preprocessor is used, but I did it just to clarify things, and for safety
> in case a similar change arises in the future.)
>
> There's a patch attached to this e-mail with the changes.  I'd appreciate
> your comments.
>
>  - E
>
>
>
> ------------------------------------------------------------------------
>
> Index: xdef_comm.f
> ===================================================================
> --- xdef_comm.f (revision 6)
> +++ xdef_comm.f (working copy)
> @@ -18,13 +18,16 @@
>  !!
>  !! SOURCE
>  
> -	! xcomm_init  definition
> +! xcomm_init  definition
>  
> +!Used to distinguish serial execution when performing reduction operations.
> +
>   subroutine xcomm_world(spaceComm)
>  #          if defined MPI || defined MPI_FFT
>  !         use mpi    
>  #          endif
>   implicit none
> + integer, parameter :: abinit_comm_self = 12345
>  #          if defined MPI || defined MPI_FFT
>             include 'mpif.h'
>  #          endif
> @@ -33,7 +36,7 @@
>  #          if defined MPI
>                 spaceComm = MPI_COMM_WORLD
>  #          else
> -               spaceComm = 0           
> +               spaceComm = abinit_comm_self
>  #          endif
>   end subroutine xcomm_world
>  
> @@ -43,6 +46,7 @@
>  !          use mpi    
>  #          endif
>   implicit none
> + integer, parameter :: abinit_comm_self = 12345
>  #          if defined MPI || defined MPI_FFT
>             include 'mpif.h'
>  #          endif
> @@ -52,18 +56,18 @@
>              if (mpi_enreg%paral_level > 1) then
>                  if (mpi_enreg%paral_level == 2) then
>                          spaceComm = MPI_COMM_WORLD
> -                        else
> +                else
>                          if (mpi_enreg%num_group_fft /= 0) then
>                                  spaceComm =  
> mpi_enreg%fft_comm(mpi_enreg%num_group_fft)
> -                                else
> -                                spaceComm = 0
> +                        else
> +                                spaceComm = MPI_COMM_SELF
>                          endif
>                  endif
> -                else
> +            else
>                  spaceComm = mpi_enreg%kpt_comm_para(mpi_enreg%ipara)
>             endif
>  #          else
> -                spaceComm = 0
> +                spaceComm = abinit_comm_self
>  #          endif
>   end subroutine xcomm_init
>  
> Index: xfuncmpi.f
> ===================================================================
> --- xfuncmpi.f  (revision 6)
> +++ xfuncmpi.f  (working copy)
> @@ -39,7 +39,7 @@
>   integer  :: ier,spaceComm
>  #          if defined MPI || defined MPI_FFT
>                 integer , allocatable :: xsum(:)
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>            !Accumulate xval on all proc. in spaceComm
>                 n1 = size(xval)
>                 allocate(xsum(n1))
> @@ -72,7 +72,7 @@
>   integer  :: ier,spaceComm
>  #          if defined MPI || defined MPI_FFT
>                 integer  :: xsum
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>            !Accumulate xval on all proc. in spaceComm
>                 call MPI_ALLREDUCE(xval,xsum,1,MPI_INTEGER,&
>            &  MPI_SUM,spaceComm,ier)
> @@ -101,7 +101,7 @@
>   integer :: xval,xsum
>   integer  :: ier,spaceComm
>  #          if defined MPI || defined MPI_FFT
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>            !Accumulate xval on all proc. in spaceComm
>                 call MPI_ALLREDUCE(xval,xsum,1,MPI_INTEGER,&
>            &  MPI_SUM,spaceComm,ier)
> @@ -132,7 +132,7 @@
>  #          if defined MPI || defined MPI_FFT
>                 integer , allocatable :: xsum(:)
>            !Accumulate xval on all proc. in spaceComm
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>                 allocate(xsum(n1))
>                 call MPI_ALLREDUCE(xval,xsum,n1,MPI_INTEGER,&
>            &  MPI_SUM,spaceComm,ier)
> @@ -164,7 +164,7 @@
>   integer  :: ier,spaceComm
>  #          if defined MPI || defined MPI_FFT
>                 integer , allocatable :: xsum(:,:)
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>            !Accumulate xval on all proc. in spaceComm
>                 n1 =size(xval,dim=1)
>                 n2 =size(xval,dim=2)
> @@ -200,7 +200,7 @@
>  #          if defined MPI || defined MPI_FFT
>                 integer , allocatable :: xsum(:,:,:)
>            !Accumulate xval on all proc. in spaceComm
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>                 n1 =size(xval,dim=1)
>                 n2 =size(xval,dim=2)
>                 n3 =size(xval,dim=3)
> @@ -236,7 +236,7 @@
>  
>  #          if defined MPI || defined MPI_FFT
>                 real(dp) , allocatable :: xsum(:)
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>         !Accumulate xval on all proc. in spaceComm
>                 n1 = size(xval)
>                 allocate(xsum(n1))
> @@ -272,7 +272,7 @@
>  #          if defined MPI || defined MPI_FFT
>                 real(dp)  :: xsum
>         !Accumulate xval on all proc. in spaceComm
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>                 call MPI_ALLREDUCE(xval,xsum,1,MPI_DOUBLE_PRECISION,&
>            &  MPI_SUM,spaceComm,ier)
>                 xval  = xsum
> @@ -303,7 +303,7 @@
>  
>  #          if defined MPI || defined MPI_FFT
>                 real(dp) , allocatable :: xsum(:)
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>         !Accumulate xval on all proc. in spaceComm
>                 allocate(xsum(n1))
>                 call MPI_ALLREDUCE(xval,xsum,n1,MPI_DOUBLE_PRECISION,&
> @@ -337,7 +337,7 @@
>  
>  #          if defined MPI || defined MPI_FFT
>                 real(dp) , allocatable :: xsum(:,:)
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>                 n1 = size(xval,dim=1)
>                 n2 = size(xval,dim=2)
>         !Accumulate xval on all proc. in spaceComm
> @@ -373,7 +373,7 @@
>  
>  #          if defined MPI || defined MPI_FFT
>                 real(dp) , allocatable :: xsum(:,:,:)
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>                 n1 = size(xval,dim=1)
>                 n2 = size(xval,dim=2)
>                 n3 = size(xval,dim=3)
> @@ -409,7 +409,7 @@
>   integer  :: ier,spaceComm
>   
>  #          if defined MPI || defined MPI_FFT
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>              !Accumulate xval on all proc. in spaceComm
>                 call MPI_ALLREDUCE(xval,xsum,n1,MPI_DOUBLE_PRECISION,&
>            &  MPI_SUM,spaceComm,ier)
> @@ -439,7 +439,7 @@
>   integer  :: ier,spaceComm
>  
>  #          if defined MPI || defined MPI_FFT
> -               if (spaceComm /= 0) then
> +               if (spaceComm /= MPI_COMM_SELF) then
>              !Accumulate xval on all proc. in spaceComm
>                 call MPI_ALLREDUCE(xval,xsum,n1,MPI_DOUBLE_PRECISION,&
>            &  MPI_SUM,spaceComm,ier)