Re: [OMPI users] restricting a job to a set of hosts

2012-07-28 Thread Erik Nelson
Reuti, >-nolocal is IMO an option where you want to execute the `mpirun` on your local login machine and want the MPI >processes to be allocated somewhere in the cluster, in case you don't have any queuing system around to manage >the resources. yes, this is exactly my understanding of the -noloc

Re: [OMPI users] restricting a job to a set of hosts

2012-07-27 Thread Reuti
Am 27.07.2012 um 03:21 schrieb Ralph Castain: > Application processes will *only* be placed on nodes included in the > allocation. The -nolocal flag is intended to ensure that no application > processes are started on the same node as mpirun in the case where that node > is included in the allo

Re: [OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Erik Nelson
I see. Thank you both for the prompt replies. On Thu, Jul 26, 2012 at 8:21 PM, Ralph Castain wrote: > Application processes will *only* be placed on nodes included in the > allocation. The -nolocal flag is intended to ensure that no application > processes are started on the same node as mpirun

Re: [OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Ralph Castain
Application processes will *only* be placed on nodes included in the allocation. The -nolocal flag is intended to ensure that no application processes are started on the same node as mpirun in the case where that node is included in the allocation. This happens, for example, with Torque, where

Re: [OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Erik Nelson
I was under the impression that the -nolocal option keeps processes off the submit host (since there may be hundreds or thousands of jobs submitted at any time, and we don't want this host to be overloaded). My understanding of what you said in you last email is that, by listing the hosts, I auto

Re: [OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Reuti
Am 26.07.2012 um 23:58 schrieb Erik Nelson: > Reuti, > > Thank you. Our queue is backed up, so it will take a little while before I > can try this. > > I assume that by specifying the nodes this way, I don't need (and it would > confuse > the system) to add -nolocal. In other words, qsub wil

Re: [OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Erik Nelson
Reuti, Thank you. Our queue is backed up, so it will take a little while before I can try this. I assume that by specifying the nodes this way, I don't need (and it would confuse the system) to add -nolocal. In other words, qsub will try to put the parent node somewhere in this set. Is this the

Re: [OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Reuti
Am 26.07.2012 um 23:48 schrieb Reuti: > Am 26.07.2012 um 23:33 schrieb Erik Nelson: > >> I have a purely parallel job that runs ~100 processes. Each process has >> ~identical >> overhead so the speed of the program is dominated by the slowest processor. >> >> For this reason, I would like to r

Re: [OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Reuti
Am 26.07.2012 um 23:33 schrieb Erik Nelson: > I have a purely parallel job that runs ~100 processes. Each process has > ~identical > overhead so the speed of the program is dominated by the slowest processor. > > For this reason, I would like to restrict the job to a specific set of > identic

[OMPI users] restricting a job to a set of hosts

2012-07-26 Thread Erik Nelson
I have a purely parallel job that runs ~100 processes. Each process has ~identical overhead so the speed of the program is dominated by the slowest processor. For this reason, I would like to restrict the job to a specific set of identical (fast) processors on our cluster. I read the FAQ on -host