Editing VSCode

[[Category:Tips]]
<span id="using-vscode"></span>

'''Note:''' [VSCodium](https://github.com/VSCodium/vscodium) is an open-source variant of Visual Studio Code that provides the same powerful features and extensibility, but without the telemetry and branding associated with the official version.

= Using VSCode =
When developing on [https://code.visualstudio.com/ VSCode], it’s important to be cautious about its CPU usage, especially when working on the login node, as it can be CPU-intensive. Certain extensions, such as the GitHub co-pilot extension, can significantly increase CPU usage. To monitor and limit CPU usage while developing on the login node, you can refer to the following articles ([https://medium.com/good-robot/use-visual-studio-code-remote-ssh-sftp-without-crashing-your-server-a1dc2ef0936d 1], [https://github.com/Microsoft/vscode/wiki/Performance-Issues 2], [https://stackoverflow.com/questions/52251058/random-high-cpu-usage 3]).

Alternatively, you can host a VSCode server on a compute node and establish an SSH tunnel to access it. This approach mostly avoids over consumption on the login node. To set this up, follow these steps:

1. Download the VSCode server release [https://github.com/microsoft/vscode/issues/135856#issuecomment-1172773063 here] and extract it in your home directory on the login node.

2. Run the following command on the login node:
  $ srun -c 8 --mem 64G --time 1-00:00:00 vscode-server-linux-x64-web/bin/code-server --accept-server-license-terms

3. Once the server starts, take note of the compute node your job lands on (e.g., babel-x-y)and the URL shown (e.g., **http://localhost:port/?tkn=...)**.

4. On the cluster login node, run the following command:
  $ ssh -NL <an available port>:0.0.0.0:port babel-x-y

5. On your local machine, run the following command:
  $ ssh -NL port:0.0.0.0:<an available port> babel

6. Open your browser and navigate to **http://localhost:port/?tkn=...** to access the VSCode server running on the compute node.

Another option is to use the remote-ssh functionality of VSCode to connect directly to a compute node. This requires an active job on the compute node. To set up the SSH configuration for connecting to the compute node, follow these steps:

1. Obtain the IP address of the compute node using the <code>ifconfig</code> command.

2. Update your SSH configuration file (<code>~/.ssh/config</code>) with the following entries:

  Host babel
    HostName babel.lti.cs.cmu.edu
    User <username>
    IdentityFile <identityfile>

  Host babel-compute-node
    HostName <node ip addr>
    User <username>
    IdentityFile <identityfile>
    ProxyJump babel

3. After configuring SSH, run VSCode natively on your local machine and use the command palette to type `Remote-SSH: Connect to Host....` Select `babel-compute-node` from the list.