A look at the modern WordPress server stack

These are the slides from a talk given at WordCamp San Diego 2016.

Do you remember when you could run a "fast" WordPress site with just an Apache server and PHP? Yeah, those were days! Things were a lot less complicated then.

Now, everything has to load lightning fast! Visitors don't have the same expectations about loading times as they used to. A slow site can have serious implications for you or your client.

You just can't have a site that feels fast to your visitors without adding a few more gears to your server engine.

During this talk, you'll learn what makes up the modern WordPress server stack. You'll see how the various pieces fit together to make your WordPress site fast. You'll leave knowing what your next steps are to get your own modern WordPress server stack.

You can read the companion article at: https://carlalexander.ca/modern-wordpress-server-stack/

Transcript

1. A look at the modern WordPress server stack
2. Carl Alexander
3. @twigpress
4. carlalexander.ca
6. Story time
7. A fast WordPress server: Linux + Apache + MySQL + PHP Once upon a time…
8. Those were the “good ol’ days”! Once upon a time…
9. Things were simpler then… Once upon a time…
10. Everything has to load fast! Nowadays…
11. Nowadays… Or there are consequences…
12. Nowadays… So the WordPress server evolved
13. The stack Nowadays…
14. Request Response
15. Request / Response Request / Response
16. Request / Response HTTP Request Web Server Browser
17. Request / Response HTTP Response Web Server Browser
18. Request / Response First HTTP response: Always HTML content
19. Request / Response Follow up HTTP requests: Required files (e.g. CSS, JS, images)
20. Request / Response Cycle continues until browser can render the page
21. Request / Response The faster it happens, the faster your website loads
22. Optimizing the cycle
23. Optimizing the cycle Can't just make a web server faster
24. Optimizing the cycle Web server is also a dispatcher
25. Optimizing the cycle Forwards requests to other services (like PHP)
26. Optimizing the cycle We need to receive as few requests as possible
27. Optimizing the cycle We need to forward as few requests as possible
28. Cycle stack elements
29. Web server
30. Web server
31. Web server Three players. 90% market share.
32. Apache: The old guard Web server
33. IIS: The Microsoft solution Web server (You can ignore this one!)
34. nginx: The new kid Web server
35. Used by Automattic since 2008 Web server
36. Used by top hosting companies Web server
37. Used by high-end WordPress agencies Web server
38. Built to handle a lot of traffic Web server
39. HTTP cache
40. HTTP cache
41. Most important element of the stack HTTP cache
42. A web server is pretty dumb HTTP cache (Well, by default)
43. Always forwards requests to PHP HTTP cache
44. PHP often generates the same response HTTP cache
45. That’s terrible! HTTP cache (PHP is our bottleneck)
46. HTTP cache solves this problem HTTP cache
47. Caches responses from PHP HTTP cache
48. Drastic reduction in cycle time HTTP cache
49. Has the widest range of options HTTP cache
50. Easiest option: Install a page caching plugin HTTP cache
51. HTTP cache • Batcache • Hyper Cache • WP Rocket • WP Super Cache • W3 Total Cache
52. Middle option: Have the web server do it HTTP cache
53. Hardest option: Add Varnish to the stack HTTP cache
54. Questions
55. Optimizing PHP
56. Optimizing PHP
57. No cached response to send back Optimizing PHP
58. Time for WordPress to do its thing Optimizing PHP
59. Turns our request into a response Optimizing PHP
60. PHP is the bottleneck Optimizing PHP
61. Latest PHP version
62. Minimum requirement: PHP 5.2 PHP version
63. Almost 10 years old! (No support since 2011) PHP version
64. PHP team hasn't been sitting idle PHP version
65. Largest improvement was from 5.3 to 5.4 (Ignoring PHP 7) PHP version
66. Opcode caching
67. PHP compiles a script each time it executes it Opcode caching
68. Caches compiled PHP code Opcode caching
69. Not bundled with PHP before 5.5 Opcode caching
70. Next generation PHP
71. Two new PHP compilers: HHVM and PHP 7 WordPress
72. Both built from the ground up WordPress
73. Incredible performance gains WordPress
74. Good news: WordPress 100% compatible WordPress
75. Bad news: Not all plugins or themes are WordPress
76. Always have a fallback to PHP 5 WordPress
77. Questions
78. Query Result
79. Query / Result Query / Result
80. PHP files don't contain any data Query / Result
81. WordPress stores all its data in a MySQL database Query / Result
82. Query / Result Query Database Server WordPress (PHP)
83. Query / Result Result Database Server WordPress (PHP)
84. Can happen a few dozen times to a few hundred times Query / Result (Talk with your developer(s) if it's the latter!)
85. Optimizing the cycle
86. Database queries take time Optimizing the cycle
87. Slows down PHP execution Optimizing the cycle
88. Can’t always control how many queries WordPress needs to do Optimizing the cycle
89. We need to make PHP wait as little as possible Optimizing the cycle
90. Cycle stack elements
91. Database server
92. Database server
93. MySQL database != MySQL server Database server
94. Multiple forked versions now Database server
95. No performance difference between versions Database server
96. Storage engines are what impact performance Database server
97. They control data management Database server
98. WordPress default: MyISAM Database server
99. Better choice: InnoDB Database server
100. Object cache
101. Object cache
102. Stores fetched or generated data Object cache
103. WordPress uses it a lot Object cache
104. Less database queries Object cache
105. But data doesn’t persist by default Object cache
106. Data can stay valid for a long time Object cache
107. Use a persistent object cache Object cache
108. Connects the object cache to a persistent data store Object cache
109. Two popular data store options Object cache
110. Memcached: The old favourite Object cache
111. Redis: The new hotness Object cache
112. Doing it yourself
113. DebOps for WordPress Doing it yourself • HHVM • MariaDB • nginx • Redis • Varnish
114. EasyEngine Doing it yourself • MariaDB • nginx • Various object cache options • Various HTTP cache options • Various PHP options
115. Trellis Doing it yourself • MariaDB • Memcached • nginx • nginx HTTP cache (optional) • PHP 7
116. Questions
117. Thank you!