VSCode on Triton

VSCode is available through Open OnDemand, and with this you can select whatever resources you want and run directly in the Slurm queue (and perform your actual calculations). If you want to connect through your own computer, it can provide a nice interface but read below.

As always when using user-contributed extensions, be cautious of what extensions you install. A malicious extension can access and/or delete all of the data available via your account.

VSCode through OOD

See also

Open OnDemand

This is useful for getting things done quickly, but running in a web browser can be limited in some cases.

VSCode remote SSH

“Remote SSH” is a nice way to work on a remote computer and provides both editing and shell access, but everything will run directly on the login node on Triton. This is OK for editing, but not for main computations (see the section above or below). To repeat: don’t use this for running big computations.

Screenshot saying "SSH: triton".

If you see this in the lower left corner (or whatever the name of your cluster SSH config is), you are connected to the login node (and should not do big calculations). It’s possible it may be different for others.

You can see connection instructions (including screenshots) at the Sigma2 instructions.

VSCode can use a regular OpenSSH configuration file, so you may as well set that up once and it can be used for everything. The basics of SSH is in Connecting via ssh and the real SSH config file info you really need is in SSH. A SSH key can allow you to connect without entering a password every time.

VSCode remote SSH host directly to interactive job

Sometimes you want more resources than the login node. This section presents a way to have VSCode directly connect to a job resource allocation on Triton - so you can do larger calculations / use more memory / etc. without interfering with others. Note that for real production calculations, you should use Serial Jobs, and not run stuff through your editor, since everything gets lost when your connection dies.

This section contains original research and may not fully work, and may only work on Linux/Mac right now.

In you ~/.ssh/config, add this block to define a server triton-vscode. For more information .ssh/config, including what these mean and what else you might need in here, see SSH:

Host triton-vscode
    ProxyCommand ssh triton /share/apps/ssh-node-proxycommand --partition=interactive --time=1:00:00
    StrictHostKeyChecking no
    UserKnownHostsFile /dev/null

# You also need a triton alias here:

Host triton
    HostName triton.aalto.fi
    # ... any other thing you need for connecting to triton.

Now, with VSCode’s Remote SSH, you can select the triton-vscode remote. It will ssh to Triton, request a job, and then directly connect to the job. Configure the job requirements in the ProxyCommand line (see Job submission - you can have multiple Host sections for different types of requirements).

Possible issues which may affect usage:

  • If the ssh connection dies, the background job will be terminated. You will lose your state and not be able to save.

  • If the job dies due to time or memory exceeded, the same as above will happen: your job will die and there is no time to save.

  • If you request a GPU node or other high resources, this is reserved the whole time even if you aren’t using them. Consider this before reserving large resources (unless you close the jobs soon), or you might get an email from us asking about resource usage.