Idle stop

An app with an idle timeout stops after that many minutes with no requests and no open connections through the gateway. An open terminal tab holds a connection, so it counts as use.

JupyterLab is the exception: its tab holds websockets open whether anyone uses it or not, so while one is open the gateway asks the Jupyter server instead. Use is what Jupyter counts (its /api/status last activity: API requests, kernel output, terminal input), and a kernel running code counts as use for as long as it runs. A visible JupyterLab tab polls the server every few seconds, which Jupyter counts as use; a hidden one (another tab in front, a minimized window) stops polling. Kernels and terminals idle for 15 minutes are shut down by the server itself, open tab or not; a kernel running code never is. The app’s files and settings are kept; it shows Stopped when idle and starts again from its card. Job runs are not affected.

config:
  idleStop:
    defaultMinutes: 0     # what a new app gets when its creator picks nothing; 0 is Off
    minMinutes: 10        # the shortest timeout people may pick
    maxMinutes: 10080     # the longest (7 days)
    allowOff: true        # whether people may pick Off; platform admins always may

It is off by default, so an upgrade never stops a shared dashboard or a long computation that nobody watches. Set defaultMinutes: 60 to free unused apps’ CPU and memory after an hour. With allowOff: false, defaultMinutes must be between minMinutes and maxMinutes.