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en:services:application_services:high_performance_computing:running_jobs_for_experienced_users [2019/09/27 09:47]
vend [GPU selection] ->https://projects.gwdg.de/projects/parallelrechnerbeschaffung-2012-13/wiki/outdated-running-jobs-for-experienced-users
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-===== Memory selection ===== 
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-Note that the following paragraph is about **selecting** nodes with enough memory for a job. The mechanism to actually **reserve** that memory does not change: The memory you are allowed to use equals memory per core times slots (-n option) requested. 
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-You can select a node either by currently available memory (mem) or by maximum available memory (maxmem). If you request complete nodes, the difference is actually very small, as a free node's available memory is close to its maximum memory. All requests are in MB. 
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-To select a node with more than about 500 GB available memory use: 
-<​code>​ 
-#BSUB -R "​mem>​500000"​ 
-</​code>​ 
-To select a node with more than about 6 GB maximum memory per core use: 
-<​code>​ 
-#BSUB -R "​maxmem/​ncpus>​6000"​ 
-</​code>​ 
-(Yes, you can do basic math in the requirement string!) 
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-It bears repeating: None of the above is a memory reservation. If you actually want to reserve "​mem"​ memory, the easiest way is to combine ''​-R "​mem>​...''​ with ''​-x''​ for an exclusive job. 
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-Finally, note that the ''​-M''​ option just denotes the memory limit of your job per core (in KB). This is of no real consequence,​ as we do not enforce these limits and it has no influence on the host selection. 
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-Besides the options shown in this article, you can of course use the options for controlling walltime limits (-W), output (-o), and your other requirements as usual. You can also continue to use job scripts instead of the command line (with the ''#​BSUB <​option>​ <​value>''​ syntax). 
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-Please consult the LSF man pages if you need further information. 
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-[[Kategorie:​ Scientific Computing]]