This document discusses strategies for scaling high traffic websites. It covers various techniques including page caching, object caching, optimizing queries and algorithms, using a search index, elastic architecture, and development workflows. Page caching can improve performance but introduces challenges around cache expiration and cookies. Object caching speeds up PHP but requires handling complexity, invalidation, optimization and eviction. The document suggests optimizing queries, testing algorithms with large data sets, and using a dedicated search index. It also discusses options for elastic architecture including load balancing, shared media, and consistency. The summary concludes by outlining components of a modern scalable stack and options for getting help implementing scalable solutions.

1. Scaling for High Traffic Sites
scalewp.io

2. About
Drew Gorton
Web Developer, Various (1998-2001)
CEO, Gorton Studios (2001-2015)
Product Owner, NodeSquirrel (2012-2015)
Director of Agency and Community Outreach, Pantheon (Current)
drew@pantheon.io
@dgorton

3. Why Scale Matters

4. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

5. Page Caching

6. Page Caching

7. Page Caching
Challenges & Takeaways
● Cache TTL and Expiration
● Fragment caching
● Cookies

8. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

9. Object Caching
An object cache speeds up PHP
execution time while lessening the
load on the database.

10. Object Cache
Challenges & Takeaways
● Complexity
● Invalidation
● Optimization
● Eviction

11. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

12. Query Performance

14. Query
Performance
Challenges & Takeaways
● Query routing
● Replication lag
● Debuggability
● Regressions

15. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

16. Algorithm
Performance

17. Algorithm
Performance
Challenges & Takeaways
● Mo’ data, Mo’ problems.
● Test with big data sets to find
problems before they hit
production.
● Avoid bloating the DOM /
blowing up the UX.
● Load data as you need it.

18. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

19. Searching for Scale
Use a dedicated search index like
Apache Solr or ElasticSearch

20. Searching for
Scale
Challenge & Takeaways
● Overriding WP_Query()
● Index Rebuilds
● Complexity

21. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

22. Elastic Architecture
Horizontal Scalability Is the Scalability That Matters

23. Traditional Options
Shared vs VM vs Cluster

24. Traditional Options at Scale
In Real Life

25. Next Generation Architecture
The Same Design, Just Add More

26. Elastic
Architecture
Challenges and Takeaways
● Load balancing
● Shared media
● Consistency

27. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

28. Development & Workflow

29. Development & Workflow

30. Development
Workflow
Challenges & Takeaways
● Environmental consistency
● Site configuration
● Local development
● Automation

31. Today’s Topics
● Page Caching
● Object Caching
● Query Performance
● Algorithm Performance
● Searching for Scale
● Elastic Architecture
● Development and Workflow
● A Real-World Scalable Architecture

32. A modern stack:
● Reverse proxy (e.g. Varnish)
● Apache or Nginx
● PHP
● Memcached or Redis
● MySQL and Database
Replication
● ElasticSearch or Solr
● Linux
● Version control (Git)
● CI server

33. If you don’t want to do it all on your own...

34. Learn more on
scalewp.io

35. Questions?
Drew Gorton
@dgorton