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

Making informed design decisions

It is not only when making decisions about trade-offs that we have to stand of the firm foundation of good performance data. After all, how can we make decisions about designing data structures for efficient memory access if we do not know how much it costs to access data in a cache-optimal order as opposed to some random order? This comes back to the first rule of performance, which you should have memorized by now: never guess about performance. This is easier said than done if our program exists as a scattering of design diagrams on a whiteboard.

You can't run a design, so how do you get measurements to guide and back up your design decisions? Some of the knowledge comes with experience. By this, I don't mean the kind of experience that says, "we have always done it this way." But you may have designed and implemented similar components and other parts of the new system. If they are reusable, they come with reliable performance...