[MPICH] mpich and pbs

[Rajeev Thakur]

> However, now it appears that the program being run is in serial. 
> For example, an 8 cpu job gets stared on two nodes (each node
> has 4 cpu's - 2 dual core opterons). We see all 8 processes running on
> the nodes. But in looking at the output it appears like a 
> serial job. I get the same results trying to use vasp and amber. 

What do you mean by "it appears like a serial job"? Do you mean
performance-wise?

Try running the cpi example from the examples directory on 8 processes. If
you see 4 hostnames from 1 machine and 4 from the other, the job should be
running ok. It's up to the OS to schedule the 4 processes on each machine.
MPI doesn't do that.

Rajeev

   

> -----Original Message-----
> From: owner-mpich-discuss at mcs.anl.gov 
> [mailto:owner-mpich-discuss at mcs.anl.gov] On Behalf Of Steve Young
> Sent: Wednesday, June 20, 2007 10:58 AM
> To: mpich-discuss at mcs.anl.gov
> Subject: [MPICH] mpich and pbs
> 
> Hello everyone,
> 	I still seem to be having an issue with getting mpich 
> to work properly.
> I have version mpich2-1.0.5 compiled. This works as expected 
> when I use
> mpiexec or mpirun. However, the nodes that jobs run on aren't in sync
> with the nodes that PBS allocates to the job. In posting to the list
> before I was informed to use the mpiexec from OSC that works 
> with PBS. I
> installed that and jobs now get started on the proper nodes that PBS
> allocates. However, now it appears that the program being run is in
> serial. For example, an 8 cpu job gets stared on two nodes (each node
> has 4 cpu's - 2 dual core opterons). We see all 8 processes running on
> the nodes. But in looking at the output it appears like a 
> serial job. I
> get the same results trying to use vasp and amber. So I'm not 
> sure what
> I could do to correct this. Any ideas?
> 
> -Steve
> 
> 
>