Book Image

Objective C Memory Management Essentials

Book Image

Objective C Memory Management Essentials

Overview of this book

Table of Contents (18 chapters)
Objective-C Memory Management Essentials
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Performance guidelines


Although iOS devices such as iPhones and iPads have a lot of memory compared to the early Nokia phones, it does not mean that you can be sloppy with regards to memory management. The iOS memory model and other mobile OSes do not include disk swap space, which are present on computer OSes, where persistent storage space is used as an extension of the memory space so that persistent storage can be used as a form of RAM for situations where low memory is encountered. So, the apps that you develop for iOS devices are more limited in the amount of memory that you can access.

Using large amounts of memory will lead to a serious degradation of system performance and triggering of the three memory warning levels, where the last warning level will lead to your application crashing. Plus, apps running under multitasking will share system memory with all other running apps that have higher priority such as the SMS application and phone application. So, you will never have 100...