Deciding if and when to setup prePuller is a tricky topic, and its partially 2i2c specific because:

• we have profileList's that allows users to configure images from a list which isn't standard jupyterhub chart behavior
• we have the configurator allowing users to update their default image

Action points

• Establish and document a policy based on our current understanding
• Consider if some documentation should also be upstreamed

Related

• JupyterHub's chart's configuration reference
• JupyterHub's chart's documentation about pulling images ahead of time users arrive
• In a93926a I see it as a bug to have prePuller enabled, even though it was good for the a workshop when several nodes were started ahead of time.
• In this comment I clarify when I think we should not have prePuller activated any more to avoid a bug like above:
  

  infrastructure/config/clusters/nasa-veda/common.values.yaml

  Lines 53 to 63 in f2eb7aa

  	prePuller:
  	# NOTE: To have prePuller enabled makes sense as long as we stick with a
  	# single image option configured. Disable prePuller if the
  	# configurator is used or a list of images is chosen from in the
  	# profileList. Otherwise its likely to delay delay startup of a user
  	# pod wanting to getting to wait for the pulling of another image.
  	#
  	continuous:
  	enabled: true
  	hook:
  	enabled: true