1. Getting to 2nd Base with your Content Delivery Network Mike Brittain Engineering Architect

2. Overview 1. Measure your performance 2. Tweak your cache TTLs 3. Cache dynamic objects 4. Cache whole pages 5. Inspect origin hits 6. Use proper HTTP headers 7. Use multiple CDNs 8. Review CDN documentation 9. Engage your vendor

3. Overview 20 Minutes

4. Overview 1. Cache dynamic objects 2. Inspect origin traffic 3. Cache HTML pages

5. Typical Setup

7. CDN Storage $$$

8. Origin Pull CDN lingo for “reverse proxy”

9. Response Headers Cache-control: max-age=3600 Last-Modified: Mon, 16 Mar … ETag: “82c7-378-8e2a” http://www.askapache.com/htaccess/apache-speed-etags.html

10. Revalidation Requests GET /images/generated.css HTTP/1.1 Host: origin.example.com If-Modified-Since: Mon, 16 Mar … If-None-Match: ”82c7-378-8e2a” HTTP/1.1 200 OK Content-Length: 35043... or... HTTP/1.1 304 Not Modified $$$ $

11. Review Origin Logs RequestsURLSize 28/images/logo.gif2 KB 17/images/nav_tabs.png5 KB 4,613/images/annual_report.ppt16 MB 31/images/flames.gif13 KB

12. Avoid Double Paying 16 MB x 4,600 @ 0.35/GB ≈ $25 (CDN) 16 MB x 4,600 @ 0.50/GB ≈ $36 (origin) $61

13. Avoid Double Paying 16 MB x 4,600 @ 0.35/GB ≈ $25 (CDN) 16 MB x 23 @ 0.50/GB ≈ $0.18 (origin) $25 - ish

14. Cache HTML Pages

16. Page built just for Mike

17. Cache HTML Pages Serve generic version to the CDN Use client-side logic for personalization

18. Cache HTML Pages Replace generic sections with tailored versions Cookies, JavaScript

19. Cache HTML Pages Track short history of user interactions Fresh data only where needed Ajax, Cookies, JavaScript

20. Cache HTML Pages Use tracking pixels for page views Real time data with Ajax, or fake it Ajax, Cookies, JavaScript

21. Cache HTML Pages Search Results, HTML frag., Public APIs, XML, JSON, RSS Do you GET it?

22. Cache HTML Pages

23. TTLs of 3 mins to 1 hr Psst… under 60 seconds is okay, too.

24. Cache HTML Pages 92%

25. Thank You Slides, etc. www.mikebrittain.com Questions mike@mikebrittain.com

26. Wait… You’re still here?

27. No, seriously… go away!

28. HTTP Headers cURL, telnet, Charles, Fiddler, Firebug, etc.

29. CDNs Fail Plan B  Split traffic between (similar) CDNs  Origin servers  Cloud storage

30. CDNs Fail

31. Amazon CloudFront: $0.17/GB* Rackspace Cloud Files: $0.22/GB JetS3t, Cyberduck, Transit, S3 Browser, S3Fox Plug-in, s3sync.rb, APIs, etc.

32. Multiple CDNs Cost vs. Performance Time Views