Geometry request usage
Once enabled, users can submit jobs with a geometry request by using the procs_bitmap=<string> resource request. procs_bitmap requires a numerical string made up of 1's and 0's. A 0 in the bitmap means the job cannot run on the core that matches the 0's index in the bitmap. The index is in reverse order of the number of cores available. If a job is submitted with procs_bitmap=1011, then the job requests a node with four free cores, and uses only cores one, two, and four.
The geometry request feature requires a node that has all cores free. A job with a geometry request cannot run on a node that has cores that are busy, even if the node has more than enough cores available to run the job.
qsub -l procs_bitmap=0011 ossl.sh
The job ossl.sh is submitted with a geometry request of 0011.
In the above example, the submitted job can run only on a node that has four cores. When a suitable node is found, the job runs exclusively on cores one and two.
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