[MPICH] standard input limited to 4096 bytes?

[William Gropp]

Which process manager are you using (mpd, gforker, remshell, or  
something else)?

It is possible that the process manager is hanging while expecting  
the program to read the stat from stdin (which it is probably  
forwarding).  If so, that's a bug that we'll fix.

Bill

On Oct 17, 2006, at 9:56 AM, Martin Kleinschmidt wrote:

>
> Hi,
>
> I'm having problems with standard input.
>
> the following program:
>
>       program  test
>
>       include 'mpif.h'
>       integer myid, nproc
>
>       write(*,*) '0'
>       call MPI_init(MPIerr)
>       write(*,*) '0a'
>       call MPI_comm_rank(MPI_comm_world,myid, MPIerr)
>       write(*,*) '0b'
>       call MPI_comm_size(MPI_comm_world,nproc,MPIerr)
>       write(*,*) '0c'
>
>       end
>
> runs correctly when started with
> mpiexec -n2 ./a.out < input_file_smaller_than_4097_bytes
>
> but hangs in call MPI_init when called with
> mpiexec -n2 ./a.out < input_file_larger_than_4096_bytes
>
> note that the program does NOT access standard input!
>
> I'm using mpich2-1.0.4p1, intel compilers 9.x, fedora core2.
>
> Is this a general problem of mpich?
> Is there any solution?
> In my "real" program, I regularly need standard input from files  
> larger
> than 4096 bytes.
>
>
> thanks!
>
>    ...martin
>