Book Image

The Art of Writing Efficient Programs

By : Fedor G. Pikus
3 (2)
Book Image

The Art of Writing Efficient Programs

3 (2)
By: Fedor G. Pikus

Overview of this book

The great free lunch of "performance taking care of itself" is over. Until recently, programs got faster by themselves as CPUs were upgraded, but that doesn't happen anymore. The clock frequency of new processors has almost peaked, and while new architectures provide small improvements to existing programs, this only helps slightly. To write efficient software, you now have to know how to program by making good use of the available computing resources, and this book will teach you how to do that. The Art of Efficient Programming covers all the major aspects of writing efficient programs, such as using CPU resources and memory efficiently, avoiding unnecessary computations, measuring performance, and how to put concurrency and multithreading to good use. You'll also learn about compiler optimizations and how to use the programming language (C++) more efficiently. Finally, you'll understand how design decisions impact performance. By the end of this book, you'll not only have enough knowledge of processors and compilers to write efficient programs, but you'll also be able to understand which techniques to use and what to measure while improving performance. At its core, this book is about learning how to learn.
Table of Contents (18 chapters)
1
Section 1 – Performance Fundamentals
7
Section 2 – Advanced Concurrency
11
Section 3 – Designing and Coding High-Performance Programs

Inefficient memory management

The subject of memory management in C++ can merit a book all of its own. There are dozens if not hundreds of papers dedicated just to the issue of the STL allocators. In this chapter, we will focus on several problems that tend to affect performance the most. Some have simple solutions; for others, we will describe the issue and outline the possible solution approaches.

There are two types of memory-related problems that you may run into in the context of performance. The first one is using too much memory: your program either runs out of memory or doesn’t meet the memory use requirements. The second problem occurs when your program becomes memory-bound: its performance is limited by the speed of memory access. Often, in these cases, the runtime of the program is directly related to how much memory it uses, and reducing the memory use also makes the program run faster.

The material presented in this section is helpful mostly for programmers...