This guide will provide you with enough basic information to run straight-forward jobs on Longleaf. Please use the table of contents to access more detailed information, or email firstname.lastname@example.org with questions.
Log in to longleaf.unc.edu
Log into longleaf.unc.edu using UNC credentials (UNC onyen and onyen password).
If you are using Linux or OS X, simply use the terminal emulator packaged with your distribution. Windows users may want to use SecureCRT or SSH Secure Shel, a secure network connection tool available to Faculty, Staff, and Students through UNC ITS Software Acquisition.
Your home directory will be:
Your scratch space will be:
Longleaf uses SLURM to schedule and submit jobs. Below are the most common methods to submit jobs to Longleaf. Note: always submit your compute jobs via SLURM.
Method 1: The Submission Script
Create a bash script using your favorite editor. If you don’t have a favorite editor, use nano (for now).
The script contains job submission options followed by application commands. Please enter the following into your script (Note: that each SBATCH switch below has two ‘-‘ characters, not one):
#!/bin/bash #SBATCH --job-name=first_slurm_job #SBATCH --ntasks=1 #SBATCH --time=1:00 #SBATCH --mem=100 echo "Hello SLURM"
Save your file and exit
nano. Submit your job using the
You have created a script,
example.shthat will ask for 1 core and 100MB of memory for 1 minute. It will name the job “first_slurm_job” and run the
Method 2: Inline Submission
If you would like to submit your job at the command line without creating a script, please try the following:
$ sbatch -t 1 -n 1 -o hello.out --wrap="echo hello SLURM"
We left out the
--mem options, and used shorthand options for
ntasks. We also specified our own output file.
If no Slurm options are specified then the defaults are:
-n 1 = 1 CPU processor
–mem-per-cpu=4800 = memory per CPU in MB
-t 60 or -t 1:00:00 or -t 0-01:00 = 60 minutes or 1 hour run time.
If you see the following error message then you used the sbatch command without the
--wrap option or a valid shell script. Use the Script submission method or Inline submission method as shown above.
/var/spool/slurmd/job1535767/slurm_script: line 445: /var/spool/slurmd/bin/util/arch.sh: No such file or directory
Submitting Interactive Jobs
Submitting interactive jobs requires the srun option
--pty as in the “srun” command shown below:
srun --x11=first --pty [my_interactive_job]
--x11-first option allows XWindows to operate between the login and compute nodes.
For example, the command below will give you an interactive bash shell session:
srun --x11=first --pty /bin/bash
Partition (Queue) Information
sinfo squeue squeue -u <onyen> squeue -u <onyen> -l
scontrol show jobid <job_id_number>
Details of Completed Job
-jbelow has a single hyphen ‘-‘, and
--formathas two hyphens ‘–‘.
sacct -j <jobid> --format=JobID,JobName,MaxRSS,Elapsed,State
man sacctfor details.
module avail module add matlab module list matlab
To save your software additions for future login sessions
module save matlab
module --help for more details.