I've recently stopped using macports so the kernel.json files I had for various IPython kernels are out of date. I have renamed ~/.ipython and removed ~/.jupyter but kernels launched are failing to start with file not found errors.
More tellingly, when I run jupyter-kernelspec list it still lists all the old kernels I had set up. Where is it getting this information from and what do I need to do to refresh/remove its cache?
After a brute force search, Jupyter stores kernel info for OS X in /Users/${USER}/Library/Jupyter/kernels. This list got copied across from my .ipython/kernels list hence renaming it made no difference.
Removing /Users/${USER}/Library/Jupyter/kernels fixes the issue.
This is the reference I was looking for: http://jupyter-client.readthedocs.org/en/latest/kernels.html#kernelspecs
This is an issue in Linux also if anyone else runs into it. Check the contents of:
~/.local/share/jupyter/kernels/
Running:
jupyter --paths
will list all of the possible locations for everything it uses to run: kernels, extensions, pidfiles, etc.
adding to jbcoe's answer, if you're using macOS, the two locations where you should expect kernels to be installed are
/Users/${USER}/Library/Jupyter/kernels
and
/usr/local/share/jupyter/kernels
You may run
jupyter kernelspec list in terminal or
!jupyter kernelspec list in a notebook cell
to see a list of available kernels and the locations.
To complete the list, in Windows (at least Win 7) it is:
System-level: C:\ProgramData\jupyter\kernels
User-level: C:\Users\[username]\AppData\Roaming\jupyter\kernels
There is a folder per env(ironment) under the kernels folder. kernel.json within each subfolder is editable to change display name(s), or other parameters.
来源：https://stackoverflow.com/questions/31976367/how-do-i-delete-refresh-available-kernels-for-ipython-jupyter-notebook-v4-0