This talk was presented by Jayesh Sidhwani at the Anthill Mini Conference in Pune. In this talk, the presenter spoke about the current state of art in building Machine Learning models and the need for computing predictions in real-time. Towards the end, the presenter talks about real-time Machine Learning use-cases at Hotstar

1. Scalable, real-time Machine Learning using
Apache Kafka

2. Agenda
● Traditional model deployment process
● 90 seconds to WoW
● Let’s process the incoming stream
● Demo
● What’s more?
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3. $ whoami
● Personalisation lead at Hotstar
● Led Data Infrastructure team at Grofers and TinyOwl
● Kafka fanboy
● Usually rant on twitter @jayeshsidhwani
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4. Machine Learning @ Hotstar
● ~150 mn users
● 4.8 mn peak concurrency
● 120K peak recommendation requests per
second
● Diverse content in diverse languages
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5. Traditional model deployment process
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Model
Training
Data Lake
Serialized
Model
Batch
Predictions
Recommendation
APIs
Offline Online
● One-day /
few-hours batch
pre-compute
● Slow time to
react

6. Sense of urgency?
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● 90 seconds to convert a new user
● To power his experience, we need to know
user’s gender, interests and more
● Need an always-thinking machine

7. Thinking streams
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Data at Rest Data in motion
● Slow
● Batch-y
● Fast
● Sub-second

8. Enter Apache Kafka
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● Kafka is a scalable,
fault-tolerant, distributed message
queue
● Producers and Consumers
● Uses
○ Real-time applications such as:
intelligent notifications, anomaly etc.
○ Asynchronous communication in
event-driven architectures
Diagram credits: http://kafka.apache.org

9. Real-time infrastructure at Hotstar
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● All clickstream data pushed
into Apache Kafka
● Apache Kafka Streams to
process events as they happen
● Incoming data available for
everyone
Intelligence
Apple
TV
iOS ANDROID Roku
STREAM PROCESSING FRAMEWORK
Filter
Window
Join
Anomaly
Machine
Learning

10. Demo
Predict whether a flight is delayed in real-time
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11. How to process a stream?
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ML

12. Advanced use-cases
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page-clicksProcessor nodes
Source / Sink nodes
video-plays
predict-gender
predict-interest 5-min trending
videos
Recommended
for You
Hotstar Streaming Platform

13. Questions?
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tech.hotstar.com