iOS and macOS Performance Tuning: Cocoa, Cocoa Touch, Objective-C, and Swift

625 Pages·2017·26.31 MB·English

by  Marcel Weiher

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iOS and macOS™ Performance
Tuning
® ® ®
Cocoa , Cocoa Touch , Objective-C , and Swift™
Marcel Weiher
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Library of Congress Number: 2016961010
Copyright © 2017 Pearson Education, Inc.
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ISBN-13: 978-0-321-84284-8
ISBN-10: 0-321-84284-7
1 17
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Contents at a Glance
Contents
About the Author
Introduction
1 CPU: Principles
2 CPU: Measurement and Tools
3 CPU: Pitfalls and Techniques
4 CPU Example: XML Parsing
5 Memory: Principles
6 Memory: Measurement and Tools
7 Memory: Pitfalls and Techniques
8 Memory Example: FilterStreams
9 Swift
10 I/O: Principles
11 I/O: Measurement and Tools
12 I/O: Pitfalls and Techniques
13 I/O: Examples
14 Graphics and UI: Principles
15 Graphics and UI: Measurement and Tools
16 Graphics and UI: Pitfalls and Techniques
17 Graphics and UI: Examples
Index
Contents
About the Author
Introduction
1 CPU: Principles
A Simple Example
The Perils of (Micro-)Benchmarking
More Integer Summing
Swift
Other Languages
The Power of Hybrids
Trends
Cost of Operations
Computational Complexity
Summary
2 CPU: Measurement and Tools
Command-Line Tools
top
time
sample
Xcode Gauges
Instruments
Setup and Data Gathering
Profiling Options
Basic Analysis
Source Code
Data Mining I: Focus
Data Mining II: Pruning
Internal Measurement
Testing
Dtrace
Optimization Beyond the Call of Duty
Summary
3 CPU: Pitfalls and Techniques
Representation
Primitive Types
Strings
Objects
Accessors
Public Access
Object Creation and Caching
Mutability and Caching
Lazy Evaluation
Caching Caveats
Pitfall: Generic (Intermediate) Representations
Arrays and Bulk Processing
Dictionaries
Messaging
IMP Caching
Forwarding
Uniformity and Optimization
Methods
Pitfall: CoreFoundation
Multicore
Threads
Work Queues
Mature Optimization
4 CPU Example: XML Parsing
An HTML Scanner
Mapping Callbacks to Messages
Objects
Objects, Cheaply
Evaluation
Tune-Ups
Optimizing the Whole Widget: MAX
MAX Implementation
Summary
5 Memory: Principles
The Memory Hierarchy
Mach Virtual Memory
Heap and Stack
Stack Allocation
Heap Allocation with malloc()
Resource Management
Garbage Collection
Foundation Object Ownership
Tracing GC
Automatic Reference Counting
Process-Level Resource Reclamation
Summary
6 Memory: Measurement and Tools
Xcode Gauges
Command-Line Tools
top
heap
leaks and malloc_debug
Internal Measurement
Memory Instruments
Leaks Instrument
Allocations
VM Tracker
Counters/PM Events
Summary
7 Memory: Pitfalls and Techniques
Reference Counting
Avoiding Leaks
Foundation Objects vs. Primitives
Smaller Structures
But What About Y2K?
Compression
Purgeable Memory
Memory and Concurrency
Architectural Considerations
Temporary Allocations and Object Caching
NSCache and libcache
Memory-Mapped Files
madvise
iOS Considerations
Optimizing ARC
Summary
8 Memory Example: FilterStreams
Unix Pipes and Filters
Object-Oriented Filters
DescriptionStream
Eliminating the Infinite Recursion from description
Stream Hierarchy
Summary
9 Swift
Swift Performance: Claims
Language Characteristics