The document discusses various techniques for caching websites to improve performance. It covers full page caching plugins like WP Super Cache and W3 Total Cache. It also discusses ways to optimize web servers like Apache and Nginx, speed up PHP parsing, use memcache for generic data storage, implement opcode caching, and do fragment caching. The goal of these caching techniques is to serve cached static content instead of dynamically generating pages each time to improve load times and server efficiency.

1. Site Caching
From Nothing To Everything
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe

2. Hi, my name is Topher
I’m a WordPress developer from
Grand Rapids MI
@topher1kenobe
Site caching, from nothing to everything
Topher DeRosia, http://XWP.co
@topher1kenobe
http://XWP.co

3. Cache
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Synonyms:
hoard, stockpile, reserve,
store, stash
Bonus Homonym: Cash

4. Why Cache?
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
End User Speed
Server Health
SEO

5. What are we fixing?
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Slow database queries
Analyze with Query Monitor:
https://wordpress.org/plugins/query-monitor/
Large, uncompressed files
Inefficient software

6. What does caching do?
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
It saves a plain html version of a
WordPress generated page.
It then serves that plain html version
instead of letting WordPress do all that
work again.
This is MUCH faster.

7. Step 1, cache all the things!
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
WP Super Cache
https://wordpress.org/plugins/wp-super-cache/
W3 Total Cache
https://wordpress.org/plugins/w3-total-cache/
Batcache
https://wordpress.org/plugins/batcache/
WP Rocket
http://wp-rocket.me/

8. Gee, zipping is cool!
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Gzip is a compression program. Good
caching plugins allow you to gzip your
cached page.
On topher1kenobe.com:

9. Watch out for SEO plugins!
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
They’re greedy, and flush the cache too
often.
On high traffic sites it can be more than
once per second.

10. Step 2, Efficient web servers
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Apache: powerful, awesome, SLOW
Nginx: fewer features, similar to Apache
for dynamic content, FAST serving
static content

11. Step 2a, reverse proxy
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Use Apache to serve dynamic pages,
Nginx or Varnish to serve static pages

12. Step 3, Speedy PHP Parser
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
mod_php: Apache module. Fast
enough.
php-fcgi: quite fast, very common
php-fpm: VERY fast, awesome.
hhvm: blindingly fast, can be buggy

13. Step 4, memcache
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Generic data storage in RAM. Super
fast.
IMPORTANT: permanently borrows
system RAM. Don’t take too much.

14. Step 5, OpCode Cache
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Stores compiled PHP in RAM, causing
the app itself to be faster.
APC (Alternative PHP Cache)
XCache
Zend OpCache
Use what your sysadmin is comfortable with
https://en.wikipedia.org/wiki/List_of_PHP_accelerators

15. Step 6, Fragment caching
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Full page caching usually isn’t much
help for people who are logged in.
1. You
2. Subscribers
3. Community members (BuddyPress, bbPress)
4. Content managers

16. Transients
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Fragments of data you can store in a
cache with PHP.
http://codex.wordpress.org/Transients_API
Results of complex queries
Results of remote data calls

17. Finding Slow Spots
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Several different plugins can help find
slow spots:
Query Monitor
https://wordpress.org/plugins/query-monitor/
Debug Bar ( many addons )
https://wordpress.org/plugins/debug-bar/

18. THANKS FOR
LISTENING
http://topher1kenobe.com
Site Caching, From Nothing To Everything
Topher DeRosia
@topher1kenobe
Follow me @topher1kenobe