The document discusses techniques for improving the performance of WordPress sites. It begins by providing background on WordPress.com and how it has grown significantly. It then discusses different hosting options for WordPress sites from shared hosting to virtual private servers (VPS) to dedicated servers. For each option, it provides recommendations for plugins, caching, and other optimizations that can be applied. It also covers more advanced techniques for scaling WordPress by using multiple servers, load balancing, object caching, and database replication. Overall, the document serves as a guide to optimizing WordPress performance across different hosting scenarios.

1. High Performance
WordPress II
Fast and secure

2. What I LOVE About
WordPress

3. About Me
• Barry Abrahamson
• Systems Wrangler, Automattic
• http://barry.wordpress.com/contact-me/

4. WordPress.com

5. WordPress.com
• Launched in August 2005

6. WordPress.com
• Launched in August 2005
• ~9 million blogs today

7. WordPress.com
• Launched in August 2005
• ~9 million blogs today
• Billions of HTTP requests per day

8. WordPress.com
• Launched in August 2005
• ~9 million blogs today
• Billions of HTTP requests per day
• Billions of MySQL queries per month

9. What is Performance?

10. What is Performance?
• Fast

11. What is Performance?
• Fast
• Scalable

12. What is Performance?
• Fast
• Scalable
• Secure

13. Lifecycle

14. Lifecycle
• Shared hosting ( 95% )

15. Lifecycle
• Shared hosting ( 95% )
• VPS (Virtual Private Server) ( < 5% )

16. Lifecycle
• Shared hosting ( 95% )
• VPS (Virtual Private Server) ( < 5% )
• Dedicated Server ( < 2% )

17. Lifecycle
• Shared hosting ( 95% )
• VPS (Virtual Private Server) ( < 5% )
• Dedicated Server ( < 2% )
• 2 Dedicated Servers ( < 1% )

18. Lifecycle
• Shared hosting ( 95% )
• VPS (Virtual Private Server) ( < 5% )
• Dedicated Server ( < 2% )
• 2 Dedicated Servers ( < 1% )
• > 2 Dedicated Servers ( < 1% )

19. Upgrade!

20. Shared Hosting

21. Shared Hosting
• FTP access (maybe SSH/SFTP)

22. Shared Hosting
• FTP access (maybe SSH/SFTP)
• No server management overhead

23. Shared Hosting
• FTP access (maybe SSH/SFTP)
• No server management overhead
• Less control and fewer options

24. Shared Hosting
• FTP access (maybe SSH/SFTP)
• No server management overhead
• Less control and fewer options
• Cheap! ($4 - $20/month)

25. Shared Hosting

26. Shared Hosting
• Run the latest version of WordPress (easy)

27. Shared Hosting
• Run the latest version of WordPress (easy)
• http://wordpress.org/hosting/

28. Shared Hosting
• Run the latest version of WordPress (easy)
• http://wordpress.org/hosting/
• Plugins and Themes directory - http://
wordpress.org/extend/

29. Shared Hosting

30. Shared Hosting
• WP Super Cache

31. Shared Hosting
• WP Super Cache
• 25 - 50x capacity/throughput increase

32. Shared Hosting
• WP Super Cache
• 25 - 50x capacity/throughput increase
• Digg, Slashdot,Yahoo Buzz

33. VPS

34. VPS
• Virtual Private Server

35. VPS
• Virtual Private Server
• Between shared and dedicated

36. VPS
• Virtual Private Server
• Between shared and dedicated
• Specific resources allocated to you (good
and bad)

37. VPS
• Virtual Private Server
• Between shared and dedicated
• Specific resources allocated to you (good
and bad)
• Usually have shell “root” access

38. VPS
• Virtual Private Server
• Between shared and dedicated
• Specific resources allocated to you (good
and bad)
• Usually have shell “root” access
• $20 - $50 / month

39. VPS

40. VPS
• Run the latest version of WordPress

41. VPS
• Run the latest version of WordPress
• WP Super Cache

42. VPS
• Run the latest version of WordPress
• WP Super Cache
• PHP Opcode Cache (APC)

43. VPS
• Run the latest version of WordPress
• WP Super Cache
• PHP Opcode Cache (APC)
• WordPress persistent object cache

44. VPS
• Apache alternatives
• CDN

45. Apache + mod_php
1 request requiring php
• Using mod_php, php
is loaded for every
request even if not
needed
• Most scaling
problems are because
of this

46. VPS

47. VPS
• Apache alternatives

48. VPS
• Apache alternatives
• CDN

49. VPS
• Apache alternatives
• CDN
• W3 Total Cache

50. VPS
• Apache alternatives
• CDN
• W3 Total Cache
• MySQL tweaking ( http://
blog.mysqltuner.com/ )

51. Dedicated Server

52. Dedicated Server
• Full control

53. Dedicated Server
• Full control
• Lots of responsibility

54. Dedicated Server
• Full control
• Lots of responsibility
• Sysadmining required

55. Dedicated Server
• Full control
• Lots of responsibility
• Sysadmining required
• Can be expensive ($100 - $1000 /month)

56. 2 Servers

57. 2 Servers
• Relatively easy to implement

58. 2 Servers
• Relatively easy to implement
• 1 web server, 1 database server

59. 2 Servers
• Relatively easy to implement
• 1 web server, 1 database server
• Web + database on each

60. 2 Servers
• Relatively easy to implement
• 1 web server, 1 database server
• Web + database on each
• Isolated resources

61. 2 Servers
• Relatively easy to implement
• 1 web server, 1 database server
• Web + database on each
• Isolated resources
• Same as single server from an application
perspective but now you have to worry
about network bottlenecks

62. Server Farm

63. Server Farm
• HyperDB

64. Server Farm
• HyperDB
• Object cache with memcached backend

65. Server Farm
• HyperDB
• Object cache with memcached backend
• Can’t use file-based caches anymore

66. Server Farm
• HyperDB
• Object cache with memcached backend
• Can’t use file-based caches anymore
• Nananana...Batcache

67. Server Farm

68. Server Farm
• Load Balancer - nginx

69. Server Farm
• Load Balancer - nginx
• Web Server - nginx

70. Server Farm
• Load Balancer - nginx
• Web Server - nginx
• PHP - php-fpm (now an official PHP
project!)

71. Server Farm
• Load Balancer - nginx
• Web Server - nginx
• PHP - php-fpm (now an official PHP
project!)
• Database - Basic MySQL replication, leave
all the complicated stuff to HyperDB.

72. Server Farm

73. Server Farm
• High availability using spread and
wackamole

74. Server Farm
• High availability using spread and
wackamole
• Scaling from 3 to 300 is relatively easy
compared to scaling from 2 to 3.

75. WordPress.com
• ~ 850 servers in 3 datacenters
• ~ 350 web servers
• ~ 300 database servers
• ~ 60 memcached servers (800GB of RAM)

76. Real World Numbers
• APC
• Empty cache - 33.5 MB RAM
• Primed cache - 6.2 MB RAM
• 60% reduction in CPU utilization
• 210 8-core servers on WordPress.com

77. Scaling Tips

78. Scaling Tips
• Most (all) things you do to scale WordPress
apply to any web app

79. Scaling Tips
• Most (all) things you do to scale WordPress
apply to any web app
• If your bottleneck is the database,
something is wrong

80. Scaling Tips
• Most (all) things you do to scale WordPress
apply to any web app
• If your bottleneck is the database,
something is wrong
• Measure twice, cut once, measure again

81. Scaling Tips
• Most (all) things you do to scale WordPress
apply to any web app
• If your bottleneck is the database,
something is wrong
• Measure twice, cut once, measure again
• Don’t optimize if you don’t need to

82. Questions?