Why is my WordPress site slow?

How to figure out why your site is slow, so you can make smart decisions on what to improve.

1. Why is my WordPress site slow? Vid Luther ZippyKid vid@zippykid.com (e-mail, gtalk) @vidluther (the tweeter) vidluther (skype) Sunday, August 26, 12
2. Why is it important? • Crappy user experience • People are impatient • 40% of people leave a site that takes longer than 3 seconds to load. • SEO Voodoo (1% factor in SERP) Sunday, August 26, 12
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4. Fat Pipes - Fat Pages? • # of requests per page is now 98 • increase in “social buttons”, analytics js, and ads. • Images account for > 50% of a page load. Sunday, August 26, 12
5. PageSpeed is not the Bible • Average page speed score dropped in 2011. • 2010 - 83% versus 2011 - 75% • A score of 85% can take 60 seconds to load “While Page Speed score is a useful measurement, it should not be considered the only indicator of a page’s performance health.” Sunday, August 26, 12
6. CDN! CDN! CDN! • Number of sites using CDN up by 17% • Average load time for a site that uses CDN? • 10.05 seconds • 9.72 without • CDN is not a catch-all Sunday, August 26, 12
7. Sources • Customers Are Won or Lost in One Second, Aberdeen Group (2008); Consumer Reaction to a Poor Online Shopping Experience, Jupiter Research (2006); The User and Business Impact of Server Delays, Additional Bytes, and HTTP Chunking in Web Search, Amazon and Google (2009); When Seconds Count, Gomez (2010) • Website Response Times, Jakob Nielsen (2010); Response Time in Man-Computer Conversational Transactions, Robert R. Miller (1968) • State of the Union for Page Speed and Website Performance, Strangeloop (2011) • Consumer Response to Travel Site Performance, PhocusWright and Akamai (2010) • HTTP Archive: Nine Months, Steve Souders • Front-End Web Performance Optimization: It isn’t over till it’s over, Web Performance Today (2011) viii See results for Target.com on line 9 of the appendix in this report. Sunday, August 26, 12
8. What can a WordPress Developer Do? • Be more educated • Educate your clients • Stop being lazy - There is no magic bullet • What worked for one site will not always work on another. • How to get educated? Sunday, August 26, 12
9. Introspection Sunday, August 26, 12
10. Free Analysis is Free • Pingdom • http://tools.pingdom.com/fpt/ Sunday, August 26, 12
11. WPT - Even Better Sunday, August 26, 12
12. Don’t act blindly • A new host won’t fix the problem • Understand what a CDN is.. (CDN not Detected? WAT???) • One test does not mean you need to act NOW!! Sunday, August 26, 12
13. Look at history (Torbit) Sunday, August 26, 12
14. Browser Analysis Sunday, August 26, 12
15. Page Load Breakdown Sunday, August 26, 12
16. What was the point of all of this? • Combine output of monitoring tools • Understand if you really need to do anything • Do it - make pages load faster Sunday, August 26, 12
17. Tools • Pingdom.com/fpt/ • webpagetest.org • torbit.com • newrelic.com • Smushkid (ZippyKid) Sunday, August 26, 12
18. SmushKid • github.com/zippykid/smushkid • Made page size go from 8MB to 5MB • reduces overall footprint on disk • smaller images == more connections • Run in background Sunday, August 26, 12