4. 0.5
0.6
0.7
0.8
0.9
Standing in Line Standing on the
edge of a virtual
cliff
Experiencing
Mobile Delays
Solving a Math
Problem
https://www.ericsson.com/res/docs/2016/mobility-report/emr-feb-2016-the-stress-of-steaming-delays.pdf
Stress
6. Fast is a Human Perception
• 100ms:
• 1s:
• 10s:
https://www.nngroup.com/articles/response-times-3-important-limits/
Perceived as instantaneous
Limit for uninterrupted train of thought: Delay is
noticed, but generally accepted
Limit for keeping focus
8. Fast is a Human Perception
• 100ms:
• 1s:
• 10s:
Perceived as instantaneous
Limit for uninterrupted train of thought: Delay is noticed,
but generally accepted
Limit for keeping focus
65ms: ranged from 34-164ms
https://calendar.perfplanet.com/2018/magic-numbers/
9. Fast is a Human Perception
• 100ms:
• 1s:
• 10s: 3-5s:
Perceived as instantaneous
Limit for uninterrupted train of thought: Delay is noticed,
but generally accepted
Limit for keeping focus
65ms: ranged from 34-164ms
10. Performance Studies
3s: 53% of Users Abandon Mobile Sites
500ms: 26% Frustration
8% Engagement
100ms: 1% Revenue Walmart & Amazon (Desktop 2001)
4% Mobile Users Throw Their Phones
https://www.doubleclickbygoogle.com/articles/mobile-speed-matters
http://bit.ly/mobileWebStress
http://www.globaldots.com/how-website-speed-affects-conversion-rates/
https://www.mobilejoomla.com/blog/172-responsive-design-vs-server-side-solutions-infographic.html
18. Profile & Benchmark Where You Are Today
Video Optimizer
developer.att.com/Video-Optimizer
WebPageTest
www.webpagetest.org
Charles Proxy
www.charlesproxy.com
25. Profile & Benchmark Where You Are Today
Video Optimizer
developer.att.com/Video-Optimizer
WebPageTest
www.webpagetest.org
Charles Proxy
www.charlesproxy.com
91. Scalable Vector Graphics (SVG)
Images drawn as shapes
infinitely scalable
XML - Can be added inline to HTML document
https://gist.github.com/hail2u/2884613?short_path=66a60ff
92. Scalable Vector Graphics (SVG)
Images drawn as shapes
infinitely scalable
XML - Can be added inline to HTML document
https://gist.github.com/hail2u/2884613?short_path=66a60ff
120. Animated GIFs
Video Tags:
<video loop autoplay muted playsinline controls = "false” src="goats.mp4”/>
Video is not pre-loaded, will be last to download
Img tags are fast!
<picture>
<source type="video/mp4" srcset=”goats.mp4">
<source type="image/webp" srcset=”goats.webp">
<img src=”goats.gif">
</picture>
https://calendar.perfplanet.com/2017/animated-gif-without-the-gif/
129. Addendum 2: Network Info
// Network type that browser uses
navigator.connection.type;
// Effective bandwidth estimate
navigator.connection.downlink
// Effective round-trip time estimate
navigator.connection.rtt
// Upper bound on the downlink speed of the first network hop
navigator.connection.downlinkMax
130. Addendum 2: Network Info
// Network type that browser uses
navigator.connection.type;
// Effective bandwidth estimate
navigator.connection.downlink
// Effective round-trip time estimate
navigator.connection.rtt
// Upper bound on the downlink speed of the first network hop
navigator.connection.downlinkMax
500 KBPS
131. Addendum 3: Base 64 Encoding
Images embedded as Base64 in your HTML/CSS/JS
• Fewer Requests
• Images Now Block Rendering of Page
• Images are 20-30% larger
• Caching is limited
• Difficult to reference more than once
https://calendar.perfplanet.com/2018/performance-anti-patterns-base64-encoding/
132. Addendum 3: Base 64 Encoding
• 91KB CSS Shared as University Template
• 48KB is SVG
• Never Appears on Any Page
Departments, colleges and other units of
the University of Nebraska–Lincoln should
use the Nebraska N as a main identifier,
not the University seal, on all publications,
invitations, websites and other electronic
media.
https://unlcms.unl.edu/wdn/templates_4.1/css/all.css?dep=4.1.36
133. Addendum 3: Base 64 Encoding
https://cdn.glowing.com/generated/css/base.474240e8485dbff13fd3652d24ef83bc.css