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Re: [Condor-users] Submit Jobs question.

2010/9/23 Edier Alberto Zapata Hernández <edalzap@xxxxxxxxx>
On Thu, Sep 23, 2010 at 3:06 PM, Ian Chesal <ichesal@xxxxxxxxxxxxxxxxxx> wrote:
2010/9/23 Edier Alberto Zapata Hernández <edalzap@xxxxxxxxx>

 I have a question about job submit:
Let's say I have 4 PCs with One QuadCore processor eachone, Condor shows them as:

And when I submit a job to run multiple times: "queue 4" for example, Condor uses Cores not processors, Is there a directive in the SubmitFile to restrict the use to Processors not Cores?

So when you submit those four jobs you never want them to all run on the same machine? You can limit them by slot:

requirements = SlotID == 1

It's going to restrict their throughput a bit because you're elimination some potential valid combinations. For example: if other jobs are running in slots 1, 3 and 4 on a machine your job won't run in slot 2 because it's bound to run in only slot 1 on any machine.
How do I run the job in the 4 PCs (using all the cores in each one?)
This question is for Vanilla, Standard and Parallel universes (Parallel = MPI)

If you  don't want Condor to advertise all 4 cores you could configure your machines with:


And then the machines would only advertise 1 slot each.

But what happend with the other 3 cores? Condor will not use them? 

Just to be clear here: *Condor* doesn't use cores, your jobs use cores. Condor will only run one job at a time on the machine, but all of the cores are accessible to the job. There are valid cases for only advertising one slot on a multi-core machine. You may not have a case here. For example: if you have a multi-threaded, CPU-intensive application you may want your machines to advertise one slot because running >1 job at time simply slows everything down as threads swap continuously.

- Ian

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