I have a two-part question. If my application is single-threaded and synchronous (e.g. a web app using Gunicorn with sync workers [1]), and occasionally I need to call functions in a library that requires an event loop, is there any downside to creating and closing the loop on-the-fly only when I call the function? In other words, is creating and destroying loops cheap? Second, if I were to switch to a multi-threaded model (e.g. Gunicorn with async workers), is my only option to start the loop at the beginning of the process, and use loop.call_soon_threadsafe()? Or can I do what I was asking about above and create and close loops on-the-fly in different threads? Is either approach much more efficient than the other? Thanks, --Chris [1] http://docs.gunicorn.org/en/latest/design.html#sync-workers