"That's silly. No one in their sane mind would serve web requests AND do heavy processing in the same thread - no matter what language" Sure you could, depends

"That's silly. No one in their sane mind would serve web requests AND do heavy processing in the same thread - no matter what language" Sure you could, depends on what you are doing.. In many cases it's fine that the request takes a second to complete, but blocking the entire server for 1 second is not. Guess you define "heavy processing" a little differently, but in event driven you can't do any (blocking) processing