JupyterHub

All the alliance clusters also support JupyterHub. JupyterHub lets you spawn a JupyterLab or Notebook session on a compute node. Either of these then lets you start a Jupyter Desktop session

Accessing

Go to https://jupyterhub.<cluster>.alliancecan.ca (https://jupyter.scinet.utoronto.ca for niagara) in your browser. Sign in with your alliance username and password. Enter you reservation details and click start

  • reservation: None unless taking part in a course (not this one) with a reservations,

  • account: ending in gpu if using a GPU (including hardware OpenGL) and cpu otherwise,

  • time: 3hrs or less (runs in the interactive queue) for faster start,

  • cores: enough cores so memory/core is 12G or less (regular memory queue) for faster start,

  • memory: at least 8GB for a desktop session (see cores note about keeping memory/core 12G or less),

  • oversubscription: select if possible (shares CPUs with other users) for faster start,

  • gpu configuration: GPU type cluster has most of for faster start, and

  • user interface: JupyterLab (Jupter Notebook is the older version before the renaming).

Once JupyterLab starts, click the Desktop icon in the launcher window. This will open a desktop session in now browser tab.

The desktop session is persistent. Closing the tab just closes the tab. It does not end the session. Clicking the Desktop icon again will just reopen the existing one. To close it pick Log out in the menu bar along the top of the Desktop. The same is true of the entire JupyterLab session. To end it, pick Log out unde the File menu in the menu bar along the top.

Software

To get a terminal pick Mate terminal under Applications followed by System Tools in the menu bar along the top. The Compute Canada (the old name for the alliance) stack is loaded by default.

If you see … relocation error: …/rebind.so … you have run into a problem caused by websockify needlessly setting an LD_PRELOAD that is incompatible with system binaries. You need to run

$ unset LD_PRELOAD

each time you open a terminal to fix this.

Unlike the graham VDI system, VirtualGL hardware accelerated OpenGL is not enabled by default. Instead it can be enable on an application-by-application basis using vglrun -d egl <command>.