[Async-sig] using asyncio in synchronous applications

[Chris Jerdonek]

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