Book Image

Delphi High Performance - Second Edition

By : Primož Gabrijelčič
5 (1)
Book Image

Delphi High Performance - Second Edition

5 (1)
By: Primož Gabrijelčič

Overview of this book

Performance matters! Users hate to use programs that are not responsive to interactions or run too slow to be useful. While becoming a programmer is simple enough, you require dedication and hard work to achieve an advanced level of programming proficiency where you know how to write fast code. This book begins by helping you explore algorithms and algorithmic complexity and continues by describing tools that can help you find slow parts of your code. Subsequent chapters will provide you with practical ideas about optimizing code by doing less work or doing it in a smarter way. The book also teaches you how to use optimized data structures from the Spring4D library, along with exploring data structures that are not part of the standard Delphi runtime library. The second part of the book talks about parallel programming. You’ll learn about the problems that only occur in multithreaded code and explore various approaches to fixing them effectively. The concluding chapters provide instructions on writing parallel code in different ways – by using basic threading support or focusing on advanced concepts such as tasks and parallel patterns. By the end of this book, you’ll have learned to look at your programs from a totally different perspective and will be equipped to effortlessly make your code faster than it is now.
Table of Contents (15 chapters)

Memory Management

In the previous chapter, I explained a few things with a lot of hand-waving. I was talking about memory being allocated but I never told you what that actually means. Now is the time to fill in the missing pieces.

Memory management is part of practically every computing system. Multiple programs must coexist inside a limited memory space, and that can only be possible if the operating system is taking care of it. When a program needs some memory—for example, to create an object—it can ask the operating system and it will give it a slice of shared memory. When an object is not needed anymore, that memory can be returned to the loving care of the operating system.

Slicing and dicing memory straight from the operating system is a relatively slow operation. In lots of cases, a memory system also doesn’t know how to return small chunks of memory. For example, if you call Windows’ VirtualAlloc function to get 20 bytes of memory, it will...