In this chapter, we have learned about server applications and how they are different. We have looked at scalability and understood why it is very important for a server application to be able to scale well. We have created an OWIN Web API application and learned to host it in an IIS web server and in a separate process. We have used Visual Studio to create load tests for our server application, checked what happens when we use good and poorly written asynchronous code, and leveraged the Apache bench command line tool to run benchmarks without Visual Studio.

We also have reviewed in detail what an I/O thread and an I/O completion port are, and found out reasons why using an asynchronous I/O is the key to building scalable server applications. To check whether a third-party code uses real asynchronous I/O, we have found a tool that shows Win32 API calls. In conclusion, we have learned about synchronization context and how we can configure continuation tasks to be run on a default task...