Stephen Cleary - Concurrency in C# Cookbook: Asynchronous, Parallel, and Multithreaded Programming

By Stephen Cleary

Copyright 2019 Stephen Cleary. All rights reserved.

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[LSI]

I think the animal on this cover, a common palm civet, is applicable to the subject of this book. I knew nothing about this animal until I saw the cover, so I looked it up. Common palm civets are considered pests because they defecate all over attics and make loud noises fighting with each other at the most inopportune times. Their anal scent glands emit a nauseating secretion. They have an endangered species rating of Least Concern, which is apparently the politically correct way of saying, Kill as many of these as you want; no one will miss them. Common palm civets enjoy eating coffee cherries, and they pass the coffee beans through. Kopi luwak, one of the most expensive coffees in the world, is made from the coffee beans extracted from civet excretions. According to the Specialty Coffee Association of America, It just tastes bad.

This makes the common palm civet a perfect mascot for concurrent and multithreaded development. To the uninitiated, concurrency and multithreading are undesirable. They make well-behaved code act up in the most horrendous ways. Race conditions and whatnot cause loud crashes (always, it seems, either in production or during a demo). Some have gone so far as to declare threads are evil and avoid concurrency completely. There are a handful of developers who have developed a taste for concurrency and use it without fear; but most developers have been burned in the past by concurrency, and that experience has left a bad taste in their mouth.

However, for modern applications, concurrency is quickly becoming a requirement. Users these days expect fully responsive interfaces, and server applications are having to scale to unprecedented levels. Concurrency addresses both of these trends.

Fortunately, there are many modern libraries that make concurrency much easier! Parallel processing and asynchronous programming are no longer exclusively the domains of wizards. By raising the level of abstraction, these libraries make responsive and scalable application development a realistic goal for every developer. If you have been burned in the past, when concurrency was extremely difficult, then I encourage you to give it another try with modern tools. We can probably never call concurrency easy, but it sure isnt as hard as it used to be!