[Beowulf] first cluster

Fri Jul 16 07:59:09 PDT 2010

On Fri, Jul 16, 2010 at 10:02:53AM +0100, Hearns, John wrote:

> As an aside, my two pence worth on this thread.

I agree, the topic seems to have shifted...

> To the original poster - you have done your research on what is needed
> for a first cluster.
> Take may advice, and that of a lot of people on this list, and contact a
> cluster vendor in your area.
> You will be surprised at how competitive the price is versus sourcing
> the parts yourself.
> And remember - people who build clusters are specialists in that task,
> you are a specialist in oceanography.

We have ordered the cluster from a local builder, and expect delivery
in about 4 weeks.  I am a servant of the Oceanographers, my specialty
is software.

Thanks for the advice.  I conclude there are no magic bullet
solutions.  One must do research, make an educated guess, and then
hold one's nose and jump in at the deep end.

There is one question that perplexes me, to which I have not found an
answer.

How does the presence of a job scheduler interact with the ability of a user to
  ssh to <head>, 
  ssh to <compute-node-n>, and then type 
  mpirun -np 64 my_application

Intuition tells me there has to be something in a cluster setup, when
it has a scheduler, that prevents a user from circumventing the
scheduler by doing something like the above.

Any hints?

> John Hearns McLaren Racing

BTW, congratulations on a great season this year.

Regards,
Douglas.
-- 
  Douglas Guptill                       voice: 902-461-9749
  Research Assistant, LSC 4640          email: douglas.guptill at dal.ca
  Oceanography Department               fax:   902-494-3877
  Dalhousie University
  Halifax, NS, B3H 4J1, Canada