I'm having an issue with

ApplicationCall.respond()

taking up to 10 seconds in some situations, how could I debug that, or what could be possible causes to look into?

My immediate suggestion would be to print shit each step of the way to figure out if throttling is happening at the framework or your own processing pipeline

That's how I got there, I have two prints around a

respond()

so I can see it's what takes the time, but I can't add prints inside that, since that's a framework method.

What engine do you use? You can try writing stress tests against a development environment to simulate production.

Netty engine. Yeah stress tests is what I will likely have to do.