Web Performance & You Dave Olsen, West Virginia University HighEdWeb Arkansas, July 26 @dmolsen, dmolsen.com
Web Performance & You - HighEdWeb Arkansas Version
Jan 27, 2015
Today, a web page can be delivered to a desktop computer, a television, or a handheld device like a tablet or a phone. While a technique like responsive design helps ensure that our web sites look good across that spectrum of screen sizes we may forget our web sites should also be able to perform equally well across that same spectrum. While more and more of our users are shifting their Internet usage to these more varied platforms and connection speeds our development practices might not be keeping up.In this session we’ll review why optimizing web performance should be an important step in the development of responsive websites. We’ll look at the tools that can help you understand and measure the performance of those sites as well as discuss front-end and server-side techniques that can be used to help you improve their performance. Finally, since the best way to test your site is to have real devices in hand, we’ll share “lessons learned” so you can set-up your own device lab similar to what we have at West Virginia University.This presentation builds upon Dave’s “Optimization for Mobile” chapter in Smashing Magazine’s “The Mobile Book.”
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Web Performance & YouDave Olsen, West Virginia UniversityHighEdWeb Arkansas, July 26
@dmolsen, dmolsen.com
slideshare.net/dmolsenwvu
This presentation will be available later today at:
Dave OlsenProfessional TechnologistWest Virginia University
About Moi
@dmolsen
The Mobile Book
• Covers everything mobile
• Produced by Smashing Media
• Chapters by Peter-Paul Koch, Stephanie Rieger, Brad Frost, Trent Walton, me & others
http://the-mobile-book.com
What I’ll Talk About
• Quick Intro About Why We Should Care About Web Perf
• How to Add Performance to Your Workflow
• Setting Up a Device Lab
Why Should You Care About Web Performance?
Part Une:
The average weight of a web page today.
Source: HTTP Archive
Images JavaScript
Flash
HTM
LC
SSOther
77%
1.3 MB
RWD sites whose small screen design weighs the same as the large screen design.
Source: Podjarny
72%
Users expect your mobile site to load as quickly as your desktop site.
71%
Source: Gomez
Bounce Rate Conversion Rate Cart Size Page Views
200ms - - - -1.2%
500ms -4.7% -1.9% - -5.7%
1000ms -8.3% -3.5% -2.1% -9.4%
Case Study: Mobile Performance Effect on Business
Source: Web Performance Today
brad’s iceberg
© Brad Frost
The way in which CSS media queries have been promoted for
mobile hides tough problems and gives developers a false
promise of a simple solution for designing for small screens.
Source: Jason Grigsby on Speakerdeck
“
” - Jason Grigsby @grigs
brad’s iceberg
© Brad Frost© Brad Frost
RWD could also mean responsible web design.
Over Downloading
Download & HideDownload & ShrinkDownload & Ignore
PRIMARY PERFORMANCE ISSUES FOR RWD
Poor Networks
High LatencyVariable Bandwidth
Packet Loss
Adding Web Performance to Your Workflow
Part Deux:
Introducing the TeamBecause performance is a team effort.
Introducing the Team
“Dave”full stack dev
“Adam”front-end dev
Any resemblance to real persons, living or dead, is purely coincidental. Serious.
Parts of a Project
The Six Parts of a Project*1. First Steps2. Design & Production3. Programming4.Testing5. Deployment6.Monitoring
* - For the purposes of this talk.
First Steps
The Six Parts of a Project1. First Steps2. Design & Production3. Programming4.Testing5. Deployment6.Monitoring
The New Project Should...1. Look cool2. Have pizzazz3. Use brand colors ...
99. Be fast98. Look good on an iPhone
First Steps
Mobile first means performance first.
First Steps
Set a Performance Budget
First Steps
A budget is a guide, not a hard & fast limit. Performance tweaks are compromises.
http://timkadlec.com/2013/01/setting-a-performance-budget/
First Steps
Best request is no request. Worst request is one that
blocks the parser.
Source: Ilya Grigorik
- Ilya Grigorik @ilyagrigorik
“
”
First Steps
Corollary: The next best request is the one not parsed.
Source: My brain
- Me @dmolsen
“”
Web Performance AssumptionsFaster is better. Smaller is better.
First Steps
Web Perf Optimization Tenets Reduce requests. Reduce asset size.
Reduce page render time.
First Steps
First Steps
Learn to Love the Inspectorhttp://bit.ly/15sWYsx
First Steps
Save Yourself a Headache &Disable Your Cache When Testing
1. First Steps2.Design & Production3. Programming4.Testing5. Deployment6.Monitoring
Design & Performance
The Six Parts of a Project
Design & Performance
Things to Keep in Mind...
Images are the devil. Consider using CSS, sprites, symbol fonts, & SVG.
display: none; is definitely the devil.
Lots of things are the devil. Just understand the trade-offs when using
social widgets, web fonts & CSS.The “devil” talk is tongue-in-cheek. Serious.
Design & Performance
Explaining the Network Panel:The Waterfall
Design & Performance
Explaining the Network Panel:Resource Size
transferred size
real size
re-order
Design & Performance
latency + download
latency
re-order
Explaining the Network Panel:Latency
Design & Performance
domcontentloaded
onload
Explaining the Network Panel:Events
Design & Performance
Your goal when using the Network Panel is to shorten & compress
the waterfall.
Remember, test the squishy too.
Design & Performance
save HAR file locally
Explaining the Network Panel:Saving Files for Comparison
Design & Performance
Explaining the Profiles Panel:CSS Selectors
Design & Performance
Explaining the Profiles Panel:CSS Selectors
CodeKit
CodeKit: Web Perf in Your Workflowhttp://incident57.com/codekit/
Design & Performance
Responsive Images
Most solutions are silly & verbose.
Focus on properly formatting images. Lazy load them & don’t
worry about “high DPI.”
Programming & Performance
The Six Parts of a Project1. First Steps2. Design & Production3.Programming4.Testing5. Deployment6.Monitoring
Programming & Performance
Things to Keep in Mind...
JavaScript libraries are devils. Consider using microjs.com or vanilla JS.
Defer loading of JavaScript. Use onTouch events when appropriate.
Reflow & repaints are the devil.
The “devil” talk is tongue-in-cheek. Serious.
Programming & Performance
Explaining the Timeline Panel
Test & Optimize Performance with jsPerfhttp://jsperf.com
Programming & Performance
Testing
The Six Parts of a Project1. First Steps2. Design & Production3. Programming4.Testing5. Deployment6.Monitoring
PageSpeed Insights Extensionhttps://developers.google.com/speed/pagespeed/insights
Testing
Remote Debugging
Testing
Google Analytics Site Speed
http://www.httpwatch.comIE & Firefox Performance Issues
Testing
Google Analytics Site Speed
http://www.slideshare.net/AndyDavies/web-page-test-beyond-the-basicsWebPagetest - Beyond the Basics
Testing
Google Analytics Site Speed
Customizing WebPagetest:Capturing Events After onLoad
Testing
Customizing WebPagetest:Blackholes for Requests
Testing
Google Analytics Site Speed
Customizing WebPagetest:Scripting & Custom Viewports
Testing
Customizing WebPageTest:Video Comparison
Testing
Customizing WebPageTest:Video Comparison - Small Viewport
Testing
charlesproxy.com
SLOWING THINGS DOWN
ThrottleCharles
Testing
Using Charles Proxyhttp://blog.cloudfour.com/using-charles-proxy-to-examine-ios-apps/
Testing
Deployment
The Six Parts of a Project1. First Steps2. Design & Production3. Programming4.Testing5.Deployment6.Monitoring
Deployment
Finally getting to “traditional” performance techniques...
Performance can’t simply be tacked onto the end of a project.
Concatenate files within reason.
Minify files as appropriate.
Make sure the server supports file compression & cache headers.
Deployment
Things to Keep in Mind...
mod_pagespeed Automates a Lothttp://developers.google.com/speed/pagespeed/mod
Deployment
The Six Parts of a Project
Monitoring
1. First Steps2. Design & Production3. Programming4.Testing5. Deployment6.Monitoring
Google Analytics’ Site Speed
Monitoring
PageSpeed Insights Extensionhttps://developers.google.com/speed/pagespeed/insights
Monitoring
Setting Up a Device LabPart Trois:
eBay MobileKarma.com Cellphone store leftoversOpen device labs
GET YOUR HANDS ON REAL DEVICES
http://flic.kr/p/7972f6
OpenDeviceLab.com
Base on:WiFi-capable, Analytics
Rank, OS, Screen Dimensions, & Cost
Suggested focus: iPod Touch, mid-level
Android, high-end Android, a tablet, Blackberry,
Windows Phone 7
HOW TO DECIDE WHICH TO GET
iPod Touch w/ RetinaSamsung Fascinate +Google Nexus One +
$537
Example:
WEB PERF TWEEPS TO FOLLOW
@ilyagrigorik
@andydavies
@souders @patmeenan
@stoyanstefanov
@tameverts @yoavweiss@scottjehl
just a sampling...
Questions?
Dave OlsenProfessional TechnologistWest Virginia University
@dmolsen
Thanks for Listening
Illustrations by Graham Curry
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