nbconvert --execute : disable timeout by default?

[takowl]

I'd like to give more people a chance to weigh in on a design decision regarding nbconvert.

Since the --execute option was added to nbconvert back in 2014 (when it was still part of IPython), it has had a configurable per-cell execution timeout. By default, code that takes longer than 30 seconds is cut off, and nbconvert fails. A different limit can be set, or the timeout can be disabled entirely, so that it will leave the code running for as long as it takes.

There is a proposal to disable the timeout by default, so people who wanted any timeout would have to set it explicitly. I think this would make sense if we were designing a new feature today, but I'm still trying to work out whether it's worth changing a default that people have had several years to get used to. If we do change it, I'd like to give warning messages first, but providing warnings doesn't necessarily mean people will see them.

Here's the issue for more in-depth discussion:
https://github.com/jupyter/nbconvert/issues/791

Thanks,
Thomas