Chapter 8. Leveraging Asynchronous Tasks

The term asynchronous programming refers to defining tasks that are executed asynchronously on different threads of execution. While this is similar to multithreading, there are a few subtle differences. Firstly, a thread or a future will remain allocated to a single operating system thread until completion. This leads to the fact that is there can only be a limited number of futures that can be executed concurrently, depending on the number of processing cores available. On the other hand, asynchronous tasks are scheduled for execution on threads from a thread pool. This way, a program can have thousands, or even millions of asynchronous tasks running concurrently. An asynchronous task can be suspended at any time, or parked, and the underlying thread of execution can be reallocated to another task. Asynchronous programming constructs also allow the definition of an asynchronous task to look like a sequence of synchronous calls, but each...