Live TrafficStateful Stream Processing 11 Online algorithms based on state • Can use Flink for...
Transcript of Live TrafficStateful Stream Processing 11 Online algorithms based on state • Can use Flink for...
Live TrafficAli Ghandi
December 2020
alighandij.github.io
www.linkedin.com/in/alighandi/
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Balad
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• Start: December 2016
• Release: May 2018
Balad
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• Team members: 110
• Users: +5 million
• POI’s: +700,000
What is Live?
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xt
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What is Live?
1 minutes window
Δx/Δt
GPS location error
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What is Live?
9:039:049:109:01
Car #1Car #2Car #3Car #4
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Change point
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Bayesian online change point detection
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let’s assume that the
‘natural chance’ of a
change point is 1/λ
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Bayesian online change point detection
Stateful Stream Processing
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Online algorithms based on state• Can use Flink for production
• Last 10 minutes of events are state
• Parameters of change point detection are state
1 minutes window 1 minutes window 1 minutes window
states states states
Parameters update
base on online data.
System recover itself
Future Work
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• Graph neural networks (GNNs)
• Road ranking
Future Work
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NLP-Topic modeling
Each road can be a document and
Events can be it’s words.
▪ Problems and Challenges (Cont.)Questions
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