[MPICH] mpiexec -soft with Sun Grid Engine

[Reuti]

Hi,

Am 21.07.2006 um 18:02 schrieb Yusong Wang:

> Hi,
>
> I am trying to take advantage of the "-soft" option on a busy cluster.
> In the Appendix D (P362) of "Using MPI-2":
> mpiexec -n 10 -soft 2:10 program
> will run the program on various number of processes, depending on what
> is available.
>
> But this option doesn't work at all on our system, even though  
> there are
> enough nodes for the lower bound in the soft option. The version of
> MPICH2 is: mpich2_mpd_sock v 1.78 2005/09/23
>
> I read the python source code for mpiexec and tried:
> mpiexec -n 10 -soft 2 program
> It does not work either.
>
> I wonder what is available for this option in the current distribution
> of MPICH2. Also, should mpiexec talk to Sun Grid Engine  
> periodically to
> see if there is enough resource to run the job with the lower bound
> number of CPUs after submission? Or just check the availability of  
> CPUs
> once at submission.

please have a look here:

http://gridengine.sunsource.net/howto/mpich2-integration/mpich2- 
integration.html

The mpd startup method isn't integrated for now with SGE, so you have  
to use one of the other startup methods.

What you have to request in SGE is a parallel environment, where you  
can give the range of slots as an argument (-pe mpich2 2-10). What in  
the end is granted for your job by SGE, you can see in your jobscript  
by accessing the variable/file $NSLOTS and $TMPDIR/machines, which  
you should also use in your mpiexec call like outlined in the Howto,  
as at this point the amount of slots and their nodes are already  
fixed by SGE.

HTH - Reuti