Jared Smith presented tips for optimizing WordPress performance. He recommends first getting the most out of existing resources through caching plugins and settings, which can improve page speeds and reduce server load. Frontend optimizations like minifying files, lazy-loading scripts, and using a content delivery network can further boost performance. For high-traffic sites, moving to managed WordPress hosting or a virtual private server provides more control and flexibility compared to shared hosting. Ongoing measurement using tools like YSlow and PageSpeed Insights helps identify remaining bottlenecks.

1. Jared Smith, BoomTown
@jaredwsmith
WordPress at Peak Performance
Originally presented at WordPress Charleston’s August 2013 meeting; revised May 2014 for WordCamp Charleston

2. Why Do We Care?
• Nobody likes a slow site — you want people
to come back, right?
• Conserving resources = less money spent on
server horsepower
• Google takes site speed into consideration for
Web searches

3. First, Get The Most Out
of What You’ve Got

4. Cache Rules Everything
Around Me
• Your web server can and should tell the
browser how to cache things like images,
scripts, and CSS stylesheets if you configure
it to do so
• Less of an issue if using a content delivery
network…more on that later!

5. Good Cache Practices
• Set far-future expires headers on images, stylesheets, and
scripts. ‘Expires’ headers tell the browser how long to hold onto an
object; setting these headers further into the future help browsers
hold onto this content longer.
• Check Cache-Control headers. These headers instruct the browser
on how to cache assets it downloads; you can fine-tune these for
specific situations as well.
• Set Entity Tags (ETags). ETags can help identify versions of an
asset to help ensure content freshness.
Plugins like W3 Total Cache can help set these for you, so no
monkeying around with the web server is necessary!

6. Caching plugins
WordPress can be tuned to do a lot less work to serve up pages,
conserving resources on your server and helping you get more mileage
out of it. Caching plugins are a great way to easily accomplish this.
• WP Super Cache is a great start for full-page caching and works
fairly well on most shared hosts; it’s easy to configure and typically
trouble-free; http://wordpress.org/plugins/wp-super-cache/
• W3 Total Cache is the most comprehensive; you can get a lot out of
it especially on a VPS or dedicated server, but it requires fine-tuned
configuration; http://wordpress.org/plugins/w3-total-cache/
Never, ever, ever run two caching plugins at the same time! You’ll
shoot yourself in the foot.

7. Tuning W3 Total Cache
• On shared hosts, there’s not typically much you can do. Disk (enhanced)
caching for pages will get you some gains.
• For those of you with Virtual Private Servers (VPS) or dedicated machines,
use APC where you can to store things like the object cache and database
cache, but watch that memory usage if you’re on a low-memory VPS.
• W3 Total Cache can integrate with many content delivery networks
including CloudFront and MaxCDN (more on CDN in a few)
• Ensure browser caching options are enabled
• Installation guide: http://wordpress.org/plugins/w3-total-cache/installation/
One size does not fit all. Certain use cases will require different caching
strategies, so be sure to test and experiment as needed!

8. Frontend Optimization
• Tuning the server and caching WordPress is great,
but if you are loading jQuery three times...
• Check for and deactivate any plugins you don’t
use -- these often litter every page load with
scripts, some unnecessary
• Make sure plugins and themes are using
wp_enqueue_script to load JavaScript; this
ensures WordPress only loads certain scripts once

9. Mind Your Scripts and
Styles
• Generally, most scripts should load at the footer of the page. Loading
scripts in the header or body (with the exception of a few, notably
Google Analytics) can block page load
• Don’t use inline CSS if you can at all help it
• Minify your CSS and JavaScript files; W3 Total Cache can do this
• Make sure gzip compression is turned on to reduce the amount of
bandwidth you use; again, W3 Total Cache makes this easy to take
care of
• Test your site’s frontend with tools like YSlow (http://
developer.yahoo.com/yslow/) and Google Page Speed (https://
developers.google.com/speed/pagespeed/)

10. Content Delivery
Networks (CDNs)
• Content delivery networks are a special kind
of cache, most often used for static assets
such as scripts, styles, and images, that
distribute your content over several nodes in
different locations
• Properly configured CDNs will route traffic to
the closest server, geographically speaking,
eliminating as much latency as possible

11. CDN Services
• Photon; part of Jetpack, free to use: distributes your media
library images over WordPress.com’s CDN, but it does not
distribute your theme files. http://wordpress.org/plugins/
jetpack/
• MaxCDN: Well supported by W3 Total Cache and overall in the
WordPress community. Many large blogs use MaxCDN and
costs are reasonable (using flat monthly fees). http://
www.maxcdn.com
• Amazon CloudFront: Distribute your static files over Amazon’s
network; costs are reasonable but aren’t flat -- you pay for the
bandwidth you use. http://aws.amazon.com/cloudfront/

12. A Few Other Items…
• Cut back on how much you write to your
access and error logs to reduce disk I/O (if at
all possible, anyway)
• Make sure you have a favicon — 404s are
expensive!
• Speaking of 404s, make sure you comb your
site occasionally for broken links or broken
images

13. Where You Host Matters
Or: Eventually, You’ll Need To Upgrade

14. The Pitfalls of Shared
Hosts
• Shared hosts are great inexpensive ways to get
started with self-hosted WordPress
• But apply some substantial traffic…and you
quickly realize that you’re getting what you pay
for.
• It’s called shared hosting for a reason: you share a
server with many, many other sites. If one makes,
say, the front page of Reddit, it’s like everyone did

15. A Few Upgrade Paths

16. Managed WordPress
Hosting
• They take care of (most) of the technical stuff
for you!
• Often no caching plugins to deal with, other
benefits such as a content delivery network
(CDN) for your static assets

17. Popular Managed Hosts
• WordPress.com is the most popular hosted service
• WPEngine: Managed WordPress hosting that gives
much more flexibility than WordPress.com. Pricing
tiered by bandwidth usage. http://
www.wpengine.com
• DreamPress: New service from DreamHost geared
directly toward WordPress hosting. Pricing flat at
$19.95/mo. http://dreamhost.com

18. Virtual Private Servers
• Your own private slice of a larger server
• Many VPS hosts give direct access to the server
for maximum flexibility
• Some VPS hosts come with a control panel similar
to shared hosts; others leave you to your own
devices
• In many cases, very painless to scale up and down
as your traffic and/or budget require

19. VPS Providers
• Many hosts with shared plans also have
VPS plans: DreamHost, HostGator are two
I’ve used
• Linode, DigitalOcean: Serious VPS for geeks
— not a lot of hand-holding but tremendous
flexibility

20. Dedicated Servers
• For the highest traffic cases (and the budgets
to match)
• A well-configured VPS can stave off the need
for a dedicated server for quite some time
• Rackspace, Softlayer and even DreamHost
and HostGator offer dedicated server plans

21. Measure!

22. Tools for Measurement
• YSlow - The gold standard for measuring site performance.
Plugs into Firefox and Chrome, tests your site for potential
pitfalls, and gives you a grade.
• Google Page Speed - Google’s page grade service works
similarly to YSlow. Integrates into Google Analytics.
• New Relic - measures app performance on the server side
as well as in the browser
• Catchpoint - even more advanced! will periodically hit pages
you define and generate pretty waterfall graphs to show you
where your bottlenecks are

23. Questions?

24. Jared Smith
jared@jaredwsmith.com
http://jaredwsmith.com
http://boomtownroi.com
!
Twitter: @jaredwsmith