Varnish: How We Do It

SF Varnish Meetup
June 1st, 2015

Transcript

1. Varnish: How we do it SF Varnish Meetup June 1st 2015 Matt Robenolt
2. Hello < me irl
3. Lead Operations Engineer
4. First Generation edge (haproxy) shield app (python) Failover
5. Why this sucked
6. Duplicate routing logic Complex Caching logic WasteD RAM for failover Why this sucked
7. Failover == lose all cache Varnish held cache rules Hard to add/remove backends Why this sucked
8. Current Generation edge shield app (python)
9. Why this is rad
10. App owns all caching logic Unified request routing Utilize RAM from all nodes Why this is rad
11. If-Modified-Since Vary on cookie values Less deploys to Varnish Why this is rad
12. 60,000 15,000 13,000 Caching funnel edge shield app
13. edge shield app Onion skin view
14. edge shield app recv pass fetch hit miss hash synth fetch deliver error Onion skin view
15. edge 60,000 req/s
16. edge Closest to users (geographically) Absorbs most traffic Blocks abuse 60,000 req/s
17. edge Makes decisions for shield Sort querystrings (boltsort/std) Promote cookies to headers 60,000 req/s
18. Cookies. as headers? Why?
19. Vary: Cookie-sessionid
20. shield 15,000 req/s
21. shield Routing to app backends Serve stale content (grace) Do If-modified-Since 15,000 req/s
22. shield Parse response cache rules Backend healthchecks Store lots of content 15,000 req/s
23. application 13,000 req/s
24. application Declare response cache rules Respond to If-modified-Since 13,000 req/s
25. WaiT. 13,000 req/s still?
26. 46% 53% 1% App Response Codes
27. 46% 53% 1% App Response Codes 304 200
28. miss Hit Hit/update If-Modified-Since Hit/IMS 200 OK 200 OK 304 Not Modified v1 v2
29. tl;dr 60k req -> 7k at app Every request thru Varinsh Complex logic written once
30. tl;dr App has complete control We still <3 haproxy Each layer worth deep dive
31. We’re hiring people who hate comptuers. disqus.com/jobs
32. Check it. HTTP for Great Good speakerdeck.com/mattrobenolt/http-for-great-good Cheating Your Way to #webscale speakerdeck.com/mattrobenolt/cheating-your-way-to-webscale
33. Questions? I have answers. ^ github.com/mattrobenolt @mattrobenolt some