Cluster:Running Gaussian in parallel

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Understand the distinction between nprocs and nprocl. nprocs is for a shared-memory (single-image) machine, whereas nprocl is for a distributed-memory (cluster) system. You want to use nprocl on all our computing systems. For example, if you want to run on eight processes (four nodes), add a line like this

%nprocl=8

to your input file. You should then specify qsub -l nodes=4:ppn=2 script on the command line to submit your PBS script with a requirement of four dual-processor machines.

Once you have the number of CPUs specified in the input file, make sure that your nodelist in GAUSS_LFLAGS is set properly. See Gaussian environment for details.

If you have a bunch of input files you want to modify, use the add_nproc.pl script in /cluster/generic/bin. First cd to the directory with your input files, and then do:

perl /cluster/generic/bin/add_nproc.pl n

where n is the number proecssors you want to run on.

After that, fire it up with $g03root/bsd/g03l.