> the GIL does not come into play at all with async. In the sense that the GIL is still held and you can have at most one path of Python code executing at a ti

> the GIL does not come into play at all with async. In the sense that the GIL is still held and you can have at most one path of Python code executing at a time regardless of whether you use async or threads, sure. Most blocking I/O was already releasing the GIL so the difference is purely in how you can design your modules; for any reasoning about performance the GIL behaves the same way whether you use asyncio or not.