.. include:: <isonum.txt>

Frequently Asked Questions
==========================

... How do I access a compute node?
    An interactive session can be started by typing :code:`srun --account=<accountname> --pty bash --login`.

... What account should I use when requesting resources?
    Faculty members should use :code:`--account=faculty`.
    Staff and collaborators should use a PI-associated account that is linked to their account. For example :code:`--account=pi-<ID>`.
    Phd students may use either :code:`--account=phd` or a PI-associated account depending on whether the research is independent research, or if it is associated with a PI.

... My job has been in the queue for a long time. Why is my job not running?
    It is possible that Mercury is overloaded and awaiting resources.
    To check the status of your job, view the output of :code:`squeue` and note the "State" column.
    
    :State=(Resources): there are currently no available resources to run your job.
    :State=(Priority): other jobs with higher priority are running before your job.
    :State=(QOSGrpBilling): your other jobs have exceeded the concurrent resource limits. Your job will be available to run as your other jobs finish.

... How do I use a Python virtual environment in Jupyter?
    You must first register the kernel using the following steps.
    Activate the virtual environment, then issue the command: :code:`ipython kernel install --user --name <kernel-name>`

Error Messages
--------------

... sbatch: error: Batch job submission failed: Memory required by task is not available
    You have requested more than the allowable memory. Modify :code:`#SBATCH --mem`

... sbatch: error: Batch job submission failed: Node count specification invalid
    You have requested more than the allowable number of nodes. Modify :code:`#SBATCH --nodes`

... sbatch: error: Batch job submission failed: More processors requested than permitted
    You have requested more than the allowable number of CPUs. Modify :code:`#SBATCH --cpus-per-task` or submit to an alternate partition that allows it.

... sbatch: error: Batch job submission failed: Requested time limit is invalid (missing or exceeds some limit)
    You have requested more than the allowable runtime for your job. Modify :code:`#SBATCH --time` or submit to an alternate partition that allows it.

... sbatch: error: Batch job submission failed: Invalid partition name specified
    Self-explanatory

... sbatch: error: Batch job submission failed: Invalid account or account/partition combination specified
    Self-explanatory.
    Make sure you have access to a particular account. :code:`sacctmgr show association where user=<BoothID>`

... sbatch: error: Batch job submission failed: Job violates accounting/QOS policy (job submit limit, user's size and/or time limits)
    Cannot have more than 100 combined jobs running+pending in queue.
    This limit is 500 for faculty-associated accounts.
    Also, make sure you have set your account type: e.g. :code:`#SBATCH --account=phd`

... slurmstepd: error: *** JOB CANCELLED AT 2018-01-01T12:00:00 DUE TO TIME LIMIT ***
    The job has exceeded the wallclock limit. Modify :code:`#SBATCH --time=` or submit to an alternate partition that allows more longer jobs.

... srun: error: Unable to create step for job: Memory required by task is not available
    Make sure you are not using nested interactive sessions.
    Interactive jobs should only be launched from a login node (mfe01 or mfe02).