Its timetostopstalling barcelonajs

It’s Time to Stop Stalling:
Doug Sillars
BarcelonaJS
September 26, 2018
Mobile/Web Performance and You
@DougSillars

Contact Me:
@DougSillars
Doug.Sillars@gmail.com
www.dougsillars.com
Doug Sillars
https://www.slideshare.net/dougsillars/
Freelance Developer Relations
Performance Audits: Web/Native
Workshops:
Performance/Images/Video

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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

How Much Do Customers Hate Delays?
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

Your Customers Demand
Mobile experiences that
are:
Immersive
Rich
Fast
This can be hard.

Cellular Networks Are High Latency Environments
• Connection Establishment 500-2500ms 50-250ms 1-10ms
• Round Trip Time (RTT) 200ms 100ms 8-50ms
3G 4G Wi-Fi

Today’s Goals
Test where your app/site is today
Common Tools
Learn best practices for speed
Learn from existing tests
See the results of performance
fixes

Testing Your Mobile Performance
Native Web
Free & Open Source Tools
Video Optimizer
https://developer.att.com/
Video-Optimizer
WebPageTest
https://www.webpagetest.org
https://webspeed.cloudinary.com

Testing With Video Optimizer
Run network traces on your
phone
1. Pick device
2. Collector type
3. Set network conditions
4. Decrypt HTTPS
5. Record screen?
6. Name
7. GO!

Video Optimizer
Video Optimizer
establishes a VPN
connection on Device
Collects all Traffic in/out
Device screen displayed
on your computer
Click Stop to end trace.
Files copied over to
computer for analysis.

Best Practices– Test Results
Connections
Files and Images
HTML
Security
Video

WebPageTest
Tests Websites on Remote
Browsers
1. Enter Website
2. Set Test Location
3. Choose Device & Browser
4. Options
5. GO!

Optimizing Content Delivery
1.Delivery Speed: Redirects

© 2017 AT&T Intellectual Property. All rights reserved. AT&T, Globe logo, Mobilizing Your World and DIRECTV are registered trademarks and service marks of AT&T Intellectual Property and/or AT&T affiliated.
companies All other marks are the property of their respective owners. AT&T Proprietary (Internal Use Only). Not for use or disclosure outside the AT&T companies except under written agreement.

1.Delivery Speed
2.Content Delivery

Text Compression
Screen filled via:
130 KB JSON file

Text Compression
130 KB JSON file
populates screen
"primaryImageUrl":"/db_photos/showcards/v5/AllPhotos/1394
9024/p13949024_b_v5_aa.jpg"
"title":"America's Got Talent"

Text Compression
131 KB Uncompressed:
• Gzip: 16 KB (88% smaller!)
• Brotli: 12 KB (91% smaller!)
Screen is populated with data and images
faster

Images

Scalable Vector Graphics (SVG)

https://commons.wikimedia.org/wiki/User:Quibik/Cleaning_up_SVG_files_manually

https://github.com/google/brotli

Images
2560 px
1440 px
1555x1200 pixels (1.8 Mpixels)

Image Pixel Count
2560 px
1440 px
720x556 pixels (0.4 Mpixels)

Image Quality
2560 px
1440 px
85% Quality

Images: Putting it Together
2560 px
1440 px
85% Quality & 720x556 pixels

Image Quality Use “In The Wild”
442,000 mobile sites
Analyzed 3/15/18

Image Quality Use “In The Wild”
Median Savings (50th percentile):
• 2.83 seconds faster page load
• 419KB less data

Image Quality Tooling
http://res.cloudinary.com/dougsillars/image/upload/c_scale,q_85,w_720/
v1517843228/bigFrankSinatraImage_c1mnff.jpg
http://res.cloudinary.com/dougsillars/image/upload/c_scale,q_auto,w_720/
v1517843228/bigFrankSinatraImage_c1mnff.jpg Auto Quality: 128 KB
91.7% savings!
http://res.cloudinary.com/dougsillars/image/upload/c_scale,q_auto,r_0,w_720/
v1517843228/bigFrankSinatraImage_c1mnff.webp
WebP: 84 KB
94.6% savings!

File Format: WebP
https://caniuse.com/#feat=webp

Images and Devices
https://twitter.com/paulcalvano/status/928751141843808256

Responsive Images
http://www.responsivebreakpoints.com/

Preview Images

Preview Images
https://github.com/technopagan/sqip

Web Usage
https://www.nngroup.com/articles/scrolling-and-attention/
https://calendar.perfplanet.com/2017/progressive-image-loading-using-intersection-observer-and-sqip/

Lazy Loading
https://www.nngroup.com/articles/scrolling-and-attention/
https://calendar.perfplanet.com/2017/progressive-image-loading-using-intersection-observer-and-sqip/

Lazy Loading Use “In The Wild”
442,000 mobile sites
Analyzed 3/15/18

Animated GIFs
Original MP4
1.4 MB

Animated GIFs
Animated GIF
3.8 MB
270% larger

Animated GIFs

Animated GIFs
MP4: 256 colors
247KB
93% smaller

Video Tags are slow:
Video is not pre-loaded, will be last to download
<video autoplay loop muted playsinline controls = "false” src="goats.mp4" />
Img tags are fast!
<picture>
<source type="video/mp4" srcset=”goats.mp4">
<source type="image/webp" srcset=”goats.webp">
<img src=”goats.gif">
</picture>
Animated GIFs
https://calendar.perfplanet.com/2017/animated-gif-without-the-gif/

54
Buffer Rage
a state of uncontrollable fury or violent
anger induced by delayed or interrupted
streaming video content
http://www.ineoquest.com/press-releases/new-research-reveals-buffer-rage-as-techs-newest-epidemic

Video Startup Delay
After 2 seconds,
every additional
second corresponds
to 5.8% increase in
abandonment
https://www.akamai.com/kr/ko/multimedia/documents/technical-publication/video-stream-quality-impacts-viewer-behavior-inferring-causality-using-quasi-experimental-designs-technical-publication.pdf

Video Startup Delay
https://www.akamai.com/kr/ko/multimedia/documents/technical-publication/video-stream-quality-impacts-viewer-behavior-inferring-causality-using-quasi-experimental-designs-technical-publication.pdf

Video
<video Preload = “auto” src="goats.mp4" />
Best to use ”metadata” or “none”

What Leads to Startup Delay?
Manifest File:
List of Available
Streams
Player Chooses a Stream Stream Manifest:
List of Video Segments
Player Downloads
Segments into buffer
Video Plays

#EXTM3U#
EXT-X-STREAM-INF:BANDWIDTH=8500000,RESOLUTION=1920x1080,sunflower1080/index1080.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=200000,RESOLUTION=416x234,sunflower234/index234.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=600000,RESOLUTION=640x360,sunflower360_600k/index360_600k.m3u8
Example Manifest file:

Video Streaming
Manifest File:
List of Available
Streams
Player selects
8.5 MBPS stream Stream Manifest:
List of Video Segments
Buffer takes a long
time to fill
Video Does Not Play
Player immediately changes the
stream choice to 600KBPS

Video Streaming: Test on Fast Wi-Fi

#EXTM3U#
Example Manifest file:
8.5 MBPS is HIGH throughput for initial streaming
Best Practice: Pick middle throughput to balance startup time and quality

As long as Video download is faster than Playback….
What Leads to Stalls?

What Leads to Stalls?
Video Download
slower than playback,
so the video stalls
Buffer is filling, but
video has not resumed

Balancing the Network with Playback
Player uses available streams to balance download with playback

Video Streaming
Large jumps in
throughput
can lead to
streaming
issues

Video Streaming
Large throughput gaps can lead to
many stream changes – which can be
visible to user

Video Streaming
#EXTM3U#

Performance Summary
1.Delivery Speed
1.CDNs
2.Reduce redirects
2.Content Delivery
1) Text Compression
2) Image Sizing, Quality and Format
3) Video Bitrate

Summary
Web:
WebPageTest https://www.webpagetest.org
WebsiteSpeedTest https://Webspeedtest.cloudinary.com
Native:
Video Optimizer https://developer.att.com/Video-Optimizer
High Performance Android Apps http://bit.ly/HighPerformanceAndroidApps
Images:
Cloudinary https://www.cloudinary.com
http://www.responsivebreakpoints.com/
Tooling

Its timetostopstalling barcelonajs

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