Error in Jupyter notebook of Feature Store demo on

Hi all,

I’ve signed up on the 30-days free Hopsworks demo trial on and obtain an error in the Feature Store demo/tour in the Jupyter notebook “FeatureStoreQuickStart.ipynb”. The last cell which launches the ML experiment produces the following error “… RecursionError: maximum recursion depth exceeded …”.

Any ideas how to fix this?

Thanks and BR,


Hi Sebastian!

Did you alter the code in any way? I can try to reproduce the issue.


Hey again! So I figured out the issue. The train_fn function in that example does not import tensorflow inside the function. Code that is executed outside the train_fn is run on the Spark Driver, so the import imported tensorflow on the driver and then it tried to serialize it over the network to the Spark Executors which failed. Hence the pickling issue.

I updated the notebook to get it working, you can find it here:

Thank you very much Robin for your help! I will check out your updated notebook asap.