Surprise! Your app is slow
because the speed of light.
Clay Smith, New Relic
@smithclay
Mobile Delivery Days 2016
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When you release an
app...
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When you get a review
like this...
"App slow in the UK. 1 star."
-BenedictC
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Who owns mobile app
network issues?
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Backend/Ops
Device/
Mobile Devs
"Stuff in the middle we don't control"
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Mobile data growth
(simplified)
Amount of data
Now In a couple years
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Global Network
Latency in Fiber
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Source Destination
Great Circle
Distance
RT Time in
Fiber
SFO London 5,375 mi 84 ms
SFO Cape Town 10,124 mi 158 ms
1 ms at speed of light = Length of Massachusetts
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After one second, your
flow of thought is interrupted.
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Milliseconds
1
10
100
1000
10000
Not Magic Interrupted Too Late
https://www.nngroup.com/articles/response-times-3-important-limits/
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App services: more cloud,
more complexity
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REST API
Auth - IdP #1
Analytics
Ad Network
Auth - IdP #2
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Move it closer?
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Datacenter/AZ
CDN
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CDNs on the Edge
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Cache static and dynamic
content + "uncached origin fetch"
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#mobileperf Idea
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When in doubt, reduce the
number of TCP connections.
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TCP: Use it again
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Use HTTP keep-alive to reuse
TCP connections.
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TCP: Create connections
faster
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TCP Fast Open can speed up
opening multiple connections.