Re: [Condor-users] [newbie] force job on multiple machines

[Nick LeRoy <nleroy@xxxxxxxxxxx>]

On Tue February 22 2005 12:43 am, Chaitanya Hazarey wrote:
> Hi,
>
>
> I have coded a small program in c to make millions of comparisons to a
> given input string , and have successfully run on the condor machines.
> My problem is that  I have got 3 idle machines but this job tends to
> run on one machine only. Can't I force condor to run the job
> simultaneously on more than one machines ?

This isn't a password crack, is it?

The above implies that your program is just a single thread of execution that 
does all processing.  If that's the case, condor can't do anything to help -- 
it doesn't "split up" a job over multiple CPUs.

If, on the other hand, you've built your program such that it process a subset 
of the string list, for example, then you can submit each subset as a 
different job, perhaps something like this:

universe = vanilla
executable = /home/myuser/bin/process
arguments = a-c
queue
arguments = d-f
queue
....

Just a rough example -- I don't know enough about your problem domain to go 
any further.  You could also look into MPI, PVM or MW.

> And whatever I do i cannot change the value of MaxHosts=1 in the
> condor_submit -long cvh_pass.cmd output, what do I have to do to
> change this setting ?

Unless your job is MPI or PVM, that's the correct behaviour.

-Nick

-- 
           <<< Knock, knock, Neo. >>>
 /`-_    Nicholas R. LeRoy               The Condor Project
{     }/ http://www.cs.wisc.edu/~nleroy  http://www.cs.wisc.edu/condor
 \    /  nleroy@xxxxxxxxxxx              The University of Wisconsin
 |_*_|   608-265-5761                    Department of Computer Sciences