CppCon 2015

Part I: Introduction to lock-free programming. We will cover the fundamentals of lock-free vs lock-based programming, explore the reasons to write lock-free programs as well as the reasons not to. We will learn, or be reminded, of the basic tools of lock-free programming and consider few simple examples. To make sure you stay on for part II, we will try something beyond the simple examples, for example, a lock-free list, just to see how insanely complex the problems can get. Part II: having been burned on the complexities of generic lock-free algorithms in part I, we take a more practical approach: assuming we are not all writing STL, what limitations can we really live with? Turns out that there are some inherent limitations imposed by the nature of the concurrent problem: is here really such a thing as “concurrent queue” (yes, sort of) and we can take advantages of these limitations (what an idea, concurrency actually makes something easier!) Then there are practical limitations that most application programmers can accept: is there really such a thing as a “lock-free queue” (may be, and you don’t need it). We will explore practical examples of (mostly) lock-free data structures, with actual implementations and performance measurements. Even if the specific limitations and simplifying assumptions used in this talk do not apply to your problem, the main idea to take away is how to find such assumptions and take advantage of them, because, chances are, you can use lock-free techniques and write code that works for you and is much simpler than what you learned before.