Puma takes a really long time to quit when debug gem is loaded

[Mathieuu]

On the puma repo, I was told to post the issue here. I am not sure which gem needs a fix though:

See puma/puma#2796

Describe the bug

Puma application takes 20 seconds to quit when it has two workers configured with fork_worker and the debug gem is loaded.

Puma config:

Please copy-paste your Puma config AND your command line options here.

To Reproduce

See that repo: https://github.com/Mathieuu/DebugPuma

I scaffold a rails app with rails new app --api and did the following changes.

Launch the server with rails s then press ctrl+c to exit the process. It hangs for 20 seconds.
Remove debug from the gemfile or fork_worker from config/puma.rb and it exits instantly.

[st0012]

I haven't get to the bottom of it, but it's because the local console UI hangs for its waitpid call in the at_exit block.

debug/lib/debug/local.rb

Line 101 in bbc5831

loop{ Process.waitpid }

[ko1]

#489 may fix it.