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- bsub -n 4 -R 'span[hosts=1]' ... will submit jobs a job requesting 4 core and (4x 4GB =) 16GB RAM), and allocate all 4 cores on one machine (This is what "span[hosts=1]" is for)
Of course, the more resource you ask, the harder to schedule the jobs, and hence the pending time will be longer.
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