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You can force your job to run exclusively on a compute node (the only
job running) by using bsub -x when you submit the job. It may take a
bit longer to run though as it will have to wait in the queue for a
compute node to become fully available.
You should also be able to use a combination of -n and -R to request a
specific number of CPU's on one host. The following example should reserve 4
CPU's for your job on one compute node:
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