What's the difference with gen_event?

[manuel-rubio]

I was reading the code and, as far as I was checking it, it looks a copy of gen_event, it's been able to register handlers for every element propagated and if it's failing it's detached. Because maybe I was missing something, I'm curious, what's the difference with gen_event?

[josevalim]

In a nutshell: gen_event runs the events for all handlers in a server process - which may be a bottleneck. telemetry runs the handlers directly in the caller.