Using multiple threads with parallel LINQ

By default, only one thread is used to execute a LINQ query. Parallel LINQ (PLINQ) is an easy way to enable multiple threads to execute a LINQ query.

Good Practice: Do not assume that using parallel threads will improve the performance of your applications. Always measure real-world timings and resource usage.

Creating an app that benefits from multiple threads

To see it in action, we will start with some code that only uses a single thread to square 2 billion integers. We will use the StopWatch type to measure the change in performance.

We will use operating system tools to monitor CPU and CPU core usage. If you do not have multiple CPUs or at least multiple cores, then this exercise won't show much!

1. Create a new console application project named LinqInParallel, add it to the workspace for this chapter, and select the project as active for OmniSharp.
2. Import the System.Diagnostics namespace...