Best Practices Using Batch at SLAC

Specify an output file
Use the -o or -oo option to bsub to specify an output file for your batch job. If you do not specify a viable file, the output will be sent via email which when multiplied by the 100s or 1000s can easily overwhelm the mail server.
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Use local scratch space
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Use local scratch space during the course of your job and copy over the results to the final location when the job finishes. Using local /scratch space is more efficient for constant writing and/or reading than nfs or AFS (i.e. over the network), and multiple batch jobs reading/writing to one nfs or AFS server can cause problems for the fileserver and everyone else who may be using it.
The amount of scratch available varies by machine type, but you can request a host with a certain amount of space with the -R option, e.g. bsub -R "scratch>10" would request a host with 10GB of scratch. A wrapper to submit your batch job is recommended which does the following:
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  –   Create a directory in /scratch using the batch job ID ($LSB_JOBID).
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  –   Copy any required input files to your /scratch directory.
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  –   Write your program output to the newly created directory.
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  –   When the program/script/command finishes copy the output file to a more permanent location.
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  –   Remove your job directory from the scratch area.
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