Interactive Jobs (srun)

The following commands will log you in to a compute node for interactive usage:

# Serial (1-core) interactive session
srun --pty bash

# Multicore (a single compute node) interactive session using several core (e.g., 4 cores)
srun -p multicore -n 4 --pty bash

# Note, if running python code that uses 'os.sched_getaffinity(0)' to determine the number
# of available cores, you should use -c rather than -n to specify the number of cores.
srun -p multicore -c 4 --pty bash

# To open a GUI app directly use the --x11 flag (can also add -p, -n as above)
srun --x11 myguiapp

# If running an MPI app via an interactive session, use the following extra flag:
srun --mpi=pmi2 -n 4 mpirun -n 4 somempiapp.exe

Note that by default the above commands will inherit any environment variables you have already loaded on the login node. If you require a clean environment on the compute node (once the srun command has logged you in to a compute node) run the following command:

module purge

You can load modulefiles on the compute node as normal using the module load command.