Pro PHP Application Performance

254 Pages·2011·10.93 MB·English

Pro PHP Application
Performance
Tuning PHP Web Projects for
Maximum Performance

■ ■ ■
Armando Padilla
and Tim Hawkins
Pro PHP Application Performance: Tuning PHP Web Projects for Maximum
Performance
Copyright © 2010 by Armando Padilla and Tim Hawkins
All rights reserved. No part of this work may be reproduced or transmitted in any form or
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ISBN-13 (pbk): 978-1-4302-2898-1
ISBN-13 (electronic): 978-1-4302-2899-8
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Development Editors: Jim Markham and Michelle Lowman
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■ CONTENTS
Affecting Your Benchmark Figures ............................................................................... 20
Geographical Location ......................................................................................................................... 20
The Traveling Packets .......................................................................................................................... 20
Response Size ...................................................................................................................................... 21
Code Complexity .................................................................................................................................. 22
Browser Behavior ................................................................................................................................. 22
Web Server Setup ................................................................................................................................ 22
Summary ....................................................................................................................... 24
■Chapter 2: Improving Client Download and Rendering Performance .................. 25
The Importance of Optimizing Responses .................................................................... 27
Firebug .......................................................................................................................... 28
Installing Firebug ................................................................................................................................. 28
Firebug Performance Tabs ................................................................................................................... 28
The Console Tab ................................................................................................................................... 30
The Net Tab .......................................................................................................................................... 32
YSlow ............................................................................................................................ 33
YSlow v2 Rulesets ................................................................................................................................ 34
Installing YSlow .................................................................................................................................... 35
Starting YSlow ..................................................................................................................................... 36
Page Speed ................................................................................................................... 39
Installing Page Speed .......................................................................................................................... 39
Page Speed at Work ............................................................................................................................. 39
Optimization Tools ........................................................................................................ 42
JavaScript Optimization ....................................................................................................................... 42
JavaScript Placement .......................................................................................................................... 43
Minification of JavaScript .................................................................................................................... 46
Minification Tools .......................................................................................................... 47
YUI Compressor ............................................................................................................. 47
Closure Compiler ........................................................................................................... 48
vi
■ CONTENTS
Reduce Resource Requests ................................................................................................................. 49
Use Server-Side Compression ............................................................................................................. 49
Image Compression ...................................................................................................... 49
Smush.it ........................................................................................................................ 50
Summary ....................................................................................................................... 52
■Chapter 3: PHP Code Optimization ...................................................................... 55
PHP Best Practices ........................................................................................................ 55
The PHP Economy ................................................................................................................................ 57
require vs. require_once ...................................................................................................................... 58
Calculating Loop Length in Advance .................................................................................................... 60
Accessing Array Elements Using foreach vs. for vs. while .................................................................. 63
File Access ........................................................................................................................................... 64
Faster Access to Object Properties ...................................................................................................... 67
Looking Under the Hood Using VLD, strace, and Xdebug .............................................. 68
Reviewing Opcode Functions with VLD ................................................................................................ 69
Using strace for C-level Tracing ........................................................................................................... 71
Identifying Bottlenecks ................................................................................................. 73
Xdebug 2: PHP Debugging Tool ............................................................................................................ 73
Validating Installation ........................................................................................................................... 75
Installing the GUI-Based Tool ............................................................................................................... 77
Summary ....................................................................................................................... 80
■Chapter 4: Opcode Caching ................................................................................. 83
Reviewing Our Roadmap ............................................................................................... 83
The PHP Life Cycle ........................................................................................................ 84
Opcode Caching Tools ................................................................................................... 86
Alternative PHP Cache ......................................................................................................................... 86
XCache ................................................................................................................................................. 95
Caching with XCache ........................................................................................................................... 97
XCache Settings ................................................................................................................................... 97
vii
■ CONTENTS
eAccelerator ......................................................................................................................................... 99
eA Settings ......................................................................................................................................... 104
Summary ..................................................................................................................... 107
■Chapter 5: Variable Caching .............................................................................. 109
Application Performance Roadmap ............................................................................ 109
The Value of Implementing Variable Caching ............................................................. 110
A Sample Project: Creating the Table ......................................................................... 112
Fetching the Records ......................................................................................................................... 114
Calculating a Database Fetch ............................................................................................................ 115
APC Caching ................................................................................................................ 119
Adding Data to Cache ......................................................................................................................... 120
Benchmarking APC ............................................................................................................................ 121
Memcached ................................................................................................................ 123
Installing Memcached ........................................................................................................................ 124
Starting Memcached Server .............................................................................................................. 124
Using Memcached with PHP .............................................................................................................. 125
Summary ..................................................................................................................... 129
■Chapter 6: Choosing the Right Web Server ....................................................... 131
Choosing Which Web Server Package Is for You ........................................................ 132
Security and Stability Are Important to You ....................................................................................... 132
Availability of Engineers with Detailed Knowledge Is Important to You ............................................. 133
Your Site Is Predominantly Static Content ......................................................................................... 133
You Are Hosting in a Managed Service .............................................................................................. 133
You Are Using Unusual PHP Extensions ............................................................................................. 133
Usage Figures for Web Servers ................................................................................... 133
Web Server Request Handling .................................................................................... 134
Web Server Hardware ................................................................................................. 136
Classifying Web Servers ............................................................................................. 136
Apache HTTPD ............................................................................................................ 137
viii
■ CONTENTS
Apache Daemon Command Line ........................................................................................................ 138
Apache Multi-processing Modules ..................................................................................................... 140
Understanding Apache Modules ................................................................................. 141
Adding Dynamic Apache Modules ...................................................................................................... 142
Removing Dynamic Apache Modules ................................................................................................. 143
Final Words on Apache ............................................................................................... 144
lighttpd ........................................................................................................................ 144
Installing lighttpd ............................................................................................................................... 144
lighttpd Configuration Settings .......................................................................................................... 148
Comparing Static Load Content ......................................................................................................... 149
Installing PHP on lighttpd ................................................................................................................... 150
Nginx ........................................................................................................................... 153
Installing Nginx .................................................................................................................................. 153
Windows Installation .......................................................................................................................... 157
Nginx As a Static Web Server ..................................................................................... 158
Installing FastCGI PHP ........................................................................................................................ 160
NGinx Benchmarking ......................................................................................................................... 162
Summary ..................................................................................................................... 163
■Chapter 7: Web Server and Delivery Optimization ............................................ 165
Determining the Performance of Your Web Server ..................................................... 166
Using ApacheTop, a Real-Time Access Log File Analyzer ................................................................. 166
Understanding the Memory Footprint of Your Application .......................................... 168
Optimizing Processes in Apache ................................................................................. 170
Controlling Apache Clients (Prefork MPM) ......................................................................................... 170
Optimizing Memory Use and Preventing Swapping ........................................................................... 171
Other Apache Configuration Tweaks ........................................................................... 172
Using .htaccess Files and AllowOverride ........................................................................................... 172
Using FollowSymlinks ........................................................................................................................ 173
Using DirectoryIndex .......................................................................................................................... 173
ix
■ CONTENTS
Hostname Lookup Off .......................................................................................................................... 174
Keep-Alive On ...................................................................................................................................... 174
Using mod_deflate to Compress Content ............................................................................................ 174
Scaling Beyond a Single Server .................................................................................. 176
Using Round-Robin DNS ...................................................................................................................... 176
Using a Load Balancer ......................................................................................................................... 176
Using Direct Server Return ................................................................................................................. 179
Sharing Sessions Between Members of a Farm ................................................................................ 180
Sharing Assets with a Shared File System ......................................................................................... 181
Sharing Assets with a Separate Asset Server ..................................................................................... 182
Sharing Assets with a Content Distribution Network ......................................................................... 182
Pitfalls of Using Distributed Architectures ................................................................. 184
Cache Coherence Issues ...................................................................................................................... 184
Cache Versioning Issues ...................................................................................................................... 184
User IP Address Tracking ..................................................................................................................... 185
Domino or Cascade Failure Effects ..................................................................................................... 186
Deployment Failures ............................................................................................................................ 187
Monitoring Your Application .......................................................................................1 87
Some Monitoring Systems for You to Investigate .............................................................................. 187
Summary .................................................................................................................... 188
■Chapter 8: Database Optimization .................................................................... 189
About MySQL ..............................................................................................................1 90
Understanding MySQL Storage Engines ..................................................................... 191
MyISAM: The Original Engine .............................................................................................................. 192
InnoDB: The Pro’s Choice ..................................................................................................................... 192
Choosing a Storage Engine .................................................................................................................. 193
Understanding How MySQL Uses Memory .................................................................1 94
InnoDB vs. MyISAM Memory Usage .................................................................................................... 194
Per Server vs. per Connection (Thread) Memory Usage ..................................................................... 195
Locating Your Configuration File ................................................................................1 97
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