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Jupyterlab – resolve error messages regarding iopub_data_rate_limit

When I worked with some ML-based text evaluation I had run across an output limit rate on the notebooks output rate:

iopub_data_rate_limit : (bytes/sec) Maximum rate at which stream output can be sent on iopub before they are limited.

I had changed it by a factor of 10 from the standard value in a file ~/.jupyter/
in my home-directory on my Linux system. When starting Jupyterlab I get error messages of the kind:

‘iopub_data_rate_limit’ has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release

and in turn

ServerApp.iopub_data_rate_limit config is deprecated in 2.0. Use ZMQChannelsWebsocketConnection.iopub_data_rate_limit.

The correction is easy. You first must create a personal configuration file for the jupyter-server. This can be done easily. At the CLI of a terminal move to the main directory of your virtual Python environment. Activate it by the usual “source bin/activate“. Then request

jupyter server --generate-config

The configuration file will then be created as ~/.jupyter/ Edit the file, uncomment and change the setting for the named parameter “ZMQChannelsWeb…… E.g. raise the value by a factor of 10. That is all. Your Jupyterlab will afterward start without the quoted error messages.

See also the documentation here.