1. Screaming Fast Wordpress
Dan Collis-Puro
Berkman Center for Internet & Society
http://blogs.law.harvard.edu/djcp
djcp@cyber.law.harvard.edu
2. Me
●Dev/sysadmin for 12 years
●Pro linux admin 9 years
●Perl / mod_perl / postgres / mysql / ruby / rails /
php
●Mostly scrappy non-profits
●Geek-of-all-trades at Berkman (
http://cyber.law.harvard.edu)
●http://blogs.law.harvard.edu/
●Help manage many servers and
apps
3. Goals
●Use minimum resources to fulfill requests
●Survive the slashdot/digg effect
●Unobtrusive
●Easy to tune
●Optimize for different platforms / audiences
●If you hit the app server, you've failed
●If you MUST hit the app server, do
what's reasonable to minimize
resources
7. Apache
●Use a reverse proxy
●Keepalive on frontend, no keepalive on backend
●Enable mod_deflate
●Set a sane MaxClients setting
●Use a lighter-weight frontend server – nginx!
●Use frontend proxy caching
●apachetop
10. Wordpress
●Two major audiences: logged in and not.
●WP-SuperCache, W3 Total Cache
●Memcached is not a panacea.
●Nor is the WP object cache.
●Disable unused plugins
●CDN for media delivery
11. Our Problem
●750+ live blogs, some heavily trafficked and quite
large
●Not too many simulateously auth'd users
●MANY spiders. Freakin' spiders!
●Mini-DDOSs each week
●ENORMOUS corpus of URLs to cache
●RSS feeds don't use feedburner
12. Our Solution
●nginx as a caching front-end proxy
●No plugins
●4 lines of code to the wordpress core
●Very flexible caching rules
●Able to cache for both audiences (sorta)
●Able to cache EVERYTHING. Period.
●Handles gzipping and logging
●Able to kill bad 'bots
13. Results
●Almost NO problems since implementation
●Atom feed from 6/sec to 2500/sec (network test)
●Atom feed from 3.95/sec to ~7000/sec (local test)
(apache 3500 / sec)
●DOUBLED network throughput (?)
●Halved memory requirements
●Able to rip out all wordpress-level
customizations and plugins.
Except one.
