I/O functions (may) internally release the GIL. If the GIL becomes a bottleneck, you are not I/O bound by definition. However, you are certainly right that not

I/O functions (may) internally release the GIL. If the GIL becomes a bottleneck, you are not I/O bound by definition. However, you are certainly right that not all server applications are I/O bound. I was a bit sloppy there.