[torqueusers] Computational load on master node?

[Tom Combs]

Hi,

I'm in the process of learning about clusters with the intent of 
building a cluster using LAM/MPI and torque. Assuming that the master 
node is not listed in the node list, does it carry any of the 
computational load of jobs that are run through the queue? It is not 
clear to me if the single threaded regions of a job are run on the 
master node or not. I suspect that one of the computational nodes 
assigned to a parallel job is assigned as the primary node where all 
single thread work is done and the other nodes assigned to the job are 
used for the parallel regions. Can someone clarify this for me?

Also, does Torque and LAM/MPI utilize a node comprised of dual 
processor, dual core Opterons efficiently? Does one configure Torque to 
see these nodes as containing 4 processors? Does a piece of MPI code 
actually use both processors in a node or does it assign two separate 
jobs to the node?

Thanks for helping a newbie!

-- 
Tom Combs                                  E-mail: combs at magnet.fsu.edu
National High Magnetic Field Laboratory    Phone: (850) 644-1657
1800 E. Paul Dirac Drive                   Tallahassee, FL 32310