It's also one thing if you want to provide SingleThreadedApp and a MultiThreadedApp instances in your package, but that should be left up to the user -- or made

It's also one thing if you want to provide SingleThreadedApp and a MultiThreadedApp instances in your package, but that should be left up to the user -- or made explicit in package docs. (We're spinning up 100 go routines!) Over a decade ago I was trying to debug why the UI written in Java was slow on solaris box. But that wasn't the primary reason. Turns out there were over 3000 java threads running at any given time. The people who wrote Java code wrapped an event class around a thread, then just started kicking off events willy-nilly. So after about 5 minutes the os had thousands of these things to deal with. There wasn't really any processing left over for anyone else.