Should I worry about “This async method lacks 'await' operators and will run synchronously” warning

Question

I have a interface which exposes some async methods. More specifically it has methods defined which return either Task or Task. I am using the async/await keywords.

Answer 1

It's perfectly reasonable that some "asynchronous" operations complete synchronously, yet still conform to the asynchronous call model for the sake of polymorphism.

A real-world example of this is with the OS I/O APIs. Asynchronous and overlapped calls on some devices always complete inline (writing to a pipe implemented using shared memory, for example). But they implement the same interface as multi-part operations which do continue in the background.