One of the best features of Akka is Akka Cluster. Akka cluster allows for building distributed applications, where one application or service spans multiple nodes. From its initial release in 2013, Akka Cluster needed a node management system to manage the Akka nodes and to provide a resilient and elastic platform. With Kubernetes Akka finally has the node management system that is has been waiting for. Akka Cluster has been designed to gracefully handle nodes leaving and joining a running cluster while continuing to run. Kubernetes adds and removes nodes as needed to increase capacity or to recover from failures. In effect, there is a perfect symbiosis between Akka Cluster and Kubernetes. In this talk, we will look at and demonstrate how Akka Java Cluster and Kubernetes work together and how together they form a beautiful relationship.

1. Hugh McKee (@mckeeh3), Developer Advocate
Akka and Kubernetes:
The beginning of a beautiful relationship

2. Hugh McKee (@mckeeh3), Developer Advocate

3. Hugh McKee (@mckeeh3), Developer Advocate

4. Hugh McKee (@mckeeh3), Developer Advocate

5. The actor model in computer science is a mathematical model of
concurrent computation that treats "actors" as the universal primitives
of concurrent computation. In response to a message that it receives,
an actor can: make local decisions, create more actors, send more
messages, and determine how to respond to the next message
received. Actors may modify their own private state, but can only affect
each other through messages (avoiding the need for any locks).
Wikipedia

6. The actor model in computer science is a mathematical model of
concurrent computation that treats "actors" as the universal primitives
of concurrent computation. In response to a message that it receives,
an actor can: make local decisions, create more actors, send more
messages, and determine how to respond to the next message
received. Actors may modify their own private state, but can only affect
each other through messages (avoiding the need for any locks).
Wikipedia

7. The actor model in computer science is a mathematical model of
concurrent computation that treats "actors" as the universal primitives
of concurrent computation. In response to a message that it receives,
an actor can: make local decisions, create more actors, send more
messages, and determine how to respond to the next message
received. Actors may modify their own private state, but can only affect
each other through messages (avoiding the need for any locks).
Wikipedia

8. Kubernetes (K8s) is an open-source system for
automating deployment, scaling, and management
of containerized applications.

9. Kubernetes (K8s) is an open-source system for
automating deployment, scaling, and management
of containerized applications.
elastic
resilient

10. Akka cluster and Kubernetes
Live demo

11. “Crop Circle”
Shows
Running Pods / JVMs

12. “Crop Circle”
Shows
Running Pods / JVMs
POD / JVM
POD / JVM
POD / JVM

13. Entity
Shard
Singleton
HTTP Server
Pod

14. Entities added as needed
Inactive entities shutdown

15. Microservice Application
Microservice

16. Resilience and Scale Demo

17. The enabler of these characteristics is a Cloud-Ready Message Driven Model.
Lightbend codified these principles into the Reactive Manifesto in 2013; 24,000+ signatories around the world so far.
Responsive Resilient Elastic
React to
Users
React to
Failures
React to
Load Variance
Low latency / High
performance
Real-time / NRT
Graceful, Non-catastrophic
Recovery
Self-Healing
Responsive in the face of
changing loads
Reactive Systems

18. The enabler of these characteristics is a Cloud-Ready Message Driven Model.
Lightbend codified these principles into the Reactive Manifesto in 2013; 24,000+ signatories around the world so far.
Responsive Resilient Elastic
React to
Users
React to
Failures
React to
Load Variance
Low latency / High
performance
Real-time / NRT
Graceful, Non-catastrophic
Recovery
Self-Healing
Responsive in the face of
changing loads
Reactive Systems

19. Java Maven K8
Project Review

20. Clustered Entity Actors

21. You
entity 64
Load Balancer
Me
entity 17
Other
entity 76

22. You
entity 64
Load Balancer
Me
entity 17
Other
entity 76

23. Clustered Entity Actors
Code Review

24. Load Balancer
Pod 1

25. Load Balancer
Pod 2Pod 1 Pod 3

26. Load Balancer
Pod 2Pod 1 Pod 3

28. Distributed Actors
Cluster Aware
Actors

29. Distributed Actors
Cluster Aware
Actors

30. Distributed Actors
Cluster Aware
Actors

31. Distributed Actors
Cluster Aware
Actors

32. Cluster Aware Actors
Code Review

33. Shard Distribution
Akka Cluster Singleton

34. Shard Distribution
Akka Cluster Singleton

35. Shard Distribution
Akka Cluster Singleton

36. Entity Distributed Sharding
Akka Cluster Sharding

37. Entity Distributed
Sharding
Akka Cluster Sharding

38. Event Sourcing & CQRS
Akka Persistence & Persistence Query

39. Event Sourcing & CQRS
Akka Persistence &
Persistence Query

40. User ID Time Event
You 64 08:11 Add Item 1567
Me 17 08:15 Add Item 3254
Other 76 08:16 Add Item 8359
You 64 08:20 Add Item 2632
Me 17 08:20 Add Item 4983
Other 76 08:24 Change Item 8359
You 64 08:25 Remove Item 1567
You 64 08:26 Add shipping address
Other 76 08:30 Add Item 2438
Me 17 08:33 Add shipping address
Me 17 08:33 Add billing address
You 64 08:35 Add billing address
Event Sourcing & CQRS

41. You
entity 64
Load Balancer
Me
entity 17
Other
entity 76

42. Akka Reactive Systems and Kubernetes
Responsive Resilient Elastic
React to
Users
React to
Failures
React to
Load Variance
Low latency / High
performance
Real-time / NRT
Graceful, Non-catastrophic
Recovery
Self-Healing
Responsive in the face of
changing loads
a beautiful relationship

43. /akka-java-cluster-openshift
/akka-java-cluster.git
/akka-java-cluster-aware.git
/akka-java-cluster-singleton.git
/akka-java-cluster-sharding.git
/akka-java-cluster-persistence.git
/akka-java-cluster-persistence-query.git
https://github.com/mckeeh3…

44. Upgrade your grey matter!
Get the free O’Reilly book by Hugh McKee,
Developer Advocate at Lightbend
https://www.lightbend.com/ebooks

45. Hugh McKee (@mckeeh3), Developer Advocate
hugh.mckee@lightbend.com
Akka and Kubernetes:
The beginning of a beautiful relationship