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Gadi processors

Gadi is NCI's primary supercomputer since January 2020. The supercomputer is composed of an assortment of processors, the majority of those are Cascade Lake processors. Different queues give access to different processors and have a different charging rate

Queue Memory Priority Charging rate per walltime-hour CPU per node Processor type
normal 192 GB Normal 2SU 48 Cascade Lake (CL), 3200 nodes
normalbw 256 GB Normal 1.25SU 28 Broadwell (BW), 800 nodes
express 192 GB High 6SU 48 Cascade Lake (CL), 3200 nodes
copyq 192 GB Normal 2SU 1 cpu jobs only Cascade Lake (CL), 3200 nodes
gpuvolta 340 GB Normal 3SU 48CPUs, 4 GPU 640 Nvidia V100 GPUs, 160 nodes

Full details of all available queues are available from the NCI help pages.

Getting an account

To get a new account at NCI, you will need to get connected to a NCI project. Before you start the process, talk to your CI or supervisor to know which project code to use. You will need to apply via NCI will send you a password via SMS once your application has been processed, this usually takes under a day to do.

Once you have an account, will allow you to ask for membership of other projects you might need. Those could be projects for additional compute time or projects to access data etc.

Connecting to Gadi

To connect to Gadi, you'll need to use a SSH connection to If you're using Windows, you'll need to use something like PuTTY, or if you're connecting from linux or mac run on the commandline (substitute abc123 with your own username)

ssh -Y

You can make a shortcut for this by editing (or creating) the file ~/.ssh/config and adding the lines:

Host              gadi
User              abc123
ForwardX11        true
ForwardX11Trusted true

This way you just need to type 'ssh gadi' to connect.

Swapping Projects

If you use more than one project you can swap between them with the command 'switchproj', e.g.

switchproj w35

will start a new shell and change your current project to w35. This is useful if you want to interactively create files that will be owned by a specific project. You can also change your default project by editing the file on Gadi ~/.config/gadi-login.conf, it should have a line like


You simply need to change the project code to the one you'd like. Then you need to log out and back in for the change to take effect. In the ~/.config/gadi-login.conf file, you can also change your default shell. That is the active shell when you log into Gadi.

Resources on Gadi

To see how much compute time you have available run the command

nci_account -P $PROJECT -q 2013.q3

To see how much storage space you have available run the command

lquota -P $PROJECT

For more information see Accounting_at_NCI.


Submitting Jobs

To run a job on the supercomputer you submit it to a job queue using the 'qsub' command. Jobs are shell script files, they contain special markers to say what resources the job needs.

As an example the script ""

#PBS -l ncpus=2
#PBS -l walltime=10:00
#PBS -l mem=1gb

echo "Hello"

says to run with 2 cpus for a maximum time of 10 minutes. The job can use up to 1 GB of memory. Anything after the #PBS lines is what gets run on the supercomputer, in this instance it just prints "Hello" (any output goes to files in the directory you submitted the job named like "", error messages go to files named like " The command '-v PROJECT' means run using the current project, you can also specify a project to use like '-v PROJECT=w35'. If the job tries to use more resources than it's asked for it will be automatically stopped. The less resources you ask for the more likely it is that your job will run quickly however, you should try to request an amount close to what the job actually uses.

See the NCI PBS documentation for more detail.

Managing Jobs

To see a list of your submitted & currently running jobs run


This also shows how much resources each job has requested & is currently using. Each job in the queue has a run id number associated with it (this is also printed when you submit a job with qsub). To get more information on a job run

qstat -s 123456 # Show any status information, e.g. why the job isn't currently running
qstat -f 123456 # Show full information, including resources requested & environment variables

To remove a job from the queue use qdel

qdel 123456 # Remove the job 123456 from the queue

Copying and moving files

In general the project code is retained when moving files from one filesystem to another om gadi (using the mv command). If you instead copy the files (using cp) then the project code is changed to be the same as the project for the directory they are being copied to if the setgid bit is set, which it often is, e.g.

$ ls -ld /scratch/v45
drwxrws--- 170 root v45 16384 May 20 20:16 '''/scratch/v45'''

the s in the group permissions indicates the setgid bit is set, which means any files created there will have the group v45, rather than your default project code, and copying creates a new file. When using mv across filesystems it will effectively do a copy and on success change the attributes to match the original and then delete the original. rsync will also do something similar depending on the options used.

See here for more details on the setgid bit