LearnR Package on ShinyApps.io Server does not work: Dealing with forked proc limits

Hello everyone,

tldr; It was suggested to us to increase the fork limit of the learnr package using the tutorial.max.forked.procs option to avoid shinyapps dot io to creash but I do not quite understand this and do not know where to place this option and what exactly to write.

we are running a learnR-based webcourse for teaching our students. We initially had a starter license but we ran into problems with the server again and again. So, we updated to a basic plan but the server is still down a lot.

It seems not to be due to an error in our scripts. When we manually restart the instance on which it is running on shinyapps.io then it usually works. So it has to do something with the server.

Others dug up the following error message:
[1] "Delaying exercise execution due to forked proc limits"

We were recommended the following:>

Specifically, this is an error arising from the learnrpackage rather than shinyapps.io specifically. Looking at the learnrchangelog, it looks like learnrcan only execute 3 forked exercises in parallel. The default limit is 3, but it can be configured using the tutorial.max.forked.procs option or the TUTORIAL_MAX_FORKED_PROCS environment variable.
If you are not worried about running out of memory, you could try increasing this limit by adjusting this environment variable. Alternatively, you could reduce the number of shared connections on a single process to limit the number of exercises running in parallel.

However, I am not an expert and do not fully understand what "forks" mean. We are not worried about running out of memory as our app is simple. But I am not sure how to use the function that was mentioned. Can anyone advise us on how to use it? It is not in the documentation, it seems.

Thank you for any support you can give.

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