> there are ways of speeding up your app that don't involve touching the Python side (caching using Redis, denormalizing, etc), but they are a lot harder to imp

> there are ways of speeding up your app that don't involve touching the Python side (caching using Redis, denormalizing, etc), but they are a lot harder to implement than asynchronous I/O. Why give up on some free performance for many types of applications? 1) I can't say I find migrating blocking code to non-blocking code trivial. The bad thing about it is that you never know what you left behind. Blocking code doesn't tell you when it's blocking your event loop. 2) Async helps apps use less memory by doing away with thread overhead in connections, but is otherwise suboptimal (hinders latency) under higher cpu load scenarios. It never was a way of getting additional "free performance" for your app.