Run task on all available cores - Windows HPC Pack 2008 R2 SP4 - job-scheduling

Question

I'm using Windows HPC Pack 2008 R2 SP4 to run a MPI application. I'm having problems getting the Job Scheduler to run the app on all available cores. Here's my code...
using (IScheduler scheduler = new Scheduler())
{
scheduler.Connect("MyCluster");
var newJob = scheduler.CreateJob();
newJob.Name = "My job";
//newJob.IsExclusive = true;
var singleTask = newJob.CreateTask();
singleTask.WorkDirectory = #"C:\MpiWorkspace";
singleTask.CommandLine = #"mpiexec MyMpiApp.exe";
newJob.AddTask(singleTask);
scheduler.SubmitJob(newJob, null, null);
}
Ran like the above I get allocated 1 (measly) core out of the 16 available across the two Compute Nodes in the cluster. The best I can get is by uncommenting the line newJob.IsExclusive = true;, which then allocates me all the cores on one of the Compute Nodes (8 cores).
If I was running from the command-line I could using the mpiexec switch /np * to use all available cores, but this appears to be overridden by the Job Scheduler.
How do I get the same effect in-code, how can I run on all available cores without explicitly declaring a minimum and maximum number of cores for the task?

Answer 1

Not sure if you have solve it. I have similar problem.
One thing I can think of is that you HPC scheduler override you affinity. Go to "Configuration" -> "Configure job scheduler policies and settings" -> "Affinity", set to "No Jobs"
you also need to add parameters to mpiexec
mpiexec -np * -al 2:L -c 8 MyMpiApp.exe
/al set the affinity
/c set cores per node
Not sure how to do it when your nodes have different number of cores.
Hope this helps