[gmx-users] problem with mpi

[Guoming Xiong]

Hi, there,

I am a biginner of gromacs. I have dowloaded and compiled the gromacs 
successfully. It runs well when use the none-mpi version. But upon 
trying the mpi version, I encounted strange situations.
The following is  what  I  did

1.  "./grompp_mpi  -np 2  -f em.mdp -s em.tpr -c out.gro -p topol.top" 
----- this step created the em.tpr successfully.

2."./mdrun_mpi  -np 2 -s em.tpr -c out.gro ..." to run the MD simulation 
by mdrun_mpi, but I just can get the following message:

0 - <NO ERROR MESSAGE> : Could not convert index 136473856 into a pointer
The index may be an incorrect argument.
Possible sources of this problem are a missing "include 'mpif.h'",
a misspelled MPI object (e.g., MPI_COM_WORLD instead of MPI_COMM_WORLD)
or a misspelled user variable for an MPI object (e.g.,
com instead of comm).
[0]  Aborting program !
[0] Aborting program!
p0_15371:  p4_error: : 9039


I can not understand it at all. Would you please tell me what mistakes I 
have made?   Many thanks.

BTW, I  was running  the code on a dual-processor linux machine.


Best regards,

Guoming Xiong