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Establishing Performance Contexts
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Ianfeather
September 28, 2014
Technology
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Establishing Performance Contexts
Segmenting your site to target specific user performance contexts
Ianfeather
September 28, 2014
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Transcript
Establishing performance contexts Ian Feather - @ianfeather
Performance at ! !
We don’t know how important speed is to our users
at a given time
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It’s not that hard to get fast
It’s not that hard to get fast
It’s not that hard to get fast
It’s not that hard to get fast
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You can use these techniques to optimise (to a certain
extent)
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Total: weight: 674 KB ! Until you scroll down
the page…
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!
Performance vs Design is all about compromise
Performance vs Design is all about compromise
You can only get as fast as the design allows
Performance Contexts
We have to accept there are things we don’t know
We are constantly required to make assumptions…
Assumption 1: Users on mobile devices want a different experience
to those on desktop
Assumption 1: Users on mobile devices want a different experience
to those on desktop Viewport !== context Viewport !== network
Assumption 2: Users want every site to load within X
seconds
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Assumption 2: Users want every site to load within X
seconds Users want a site to load in-line with their expectations
Serving the same experience across multiple unknowns is a compromise
Currently we don’t have the tools to do anything about
this
But… ! The Web is for everyone
How can we determine a user’s performance context?
Why not ask them?
Hostel Mode
http://blog.chriszacharias.com/page-weight-matters
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“We even burned through our monthly data plans in 40
minutes.”
Light Mode Default
Segmenting in to two ‘modes’ can be very powerful but…
Are we still making assumptions?
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Did we ever ask users with retina screens if they
want a slower experience?
And are we still compromising?
We can’t leverage the best of the platform… whilst limiting
page weight.
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Light Mode Default
Light Mode Default Enhanced
Segmenting allows us to design focused User Experiences
Asking the user
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How could this look?
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Implementation Advice
Don’t build three different websites!
Abstract out the development complexity
if('querySelector' in document && 'localStorage' in window && 'addEventListener' in
window && 'classList' in document.documentElement && lpHostelMode() !== "light") { } Global feature switches
<div class=“my-module”> <h1>{{ moduleTitle }}</h1> {{ img_tag(moduleImage) }} <p>{{ moduleContent
}}</p> </div> Authoring must stay the same
def img_tag(image_url, opts={}) return if @hostelMode ! image_tag(image_url, opts) end
Use helpers to abstract switches
Stateless vs Stateful
Consider the preloader
Future: Could the browser expose these user options?
Recap
You can only get as fast as the design allows
Your application may be entirely inaccessible to parts of the
world
Segmenting the user experience can be very powerful
Don’t guess. Ask.
Don’t do it at the expense of complexity
Thank you Ian Feather - @ianfeather
Creative Commons ! ! ! Arrano : https://flic.kr/p/4WjZDf Patrick Quinn-Graham
(thepatrick): https://flic.kr/p/Tk4Ha Leonardo Rizzi (L1010913): https://flic.kr/p/cVRiZm