Akka.NET @ London.NET

@petabridge Petabridge.com

Concurrency Without the Pain

An Intro to Akka.NET & Actor Model

#AkkaDotNet @ #LDNUG

Andrew Skotzko Co-‐founder — Petabridge


Why should we care about

concurrency?


1970 -‐ 2005








TANSTAAFL “There ain’t no such thing as a free lunch.” —R. A. Heinlein, The Moon Is a Harsh Mistress


What the hell are you talking about?


Concurrency.

We needs it.


So why is this hard?


How to Write Multithreaded Code


Shared State Programming Sucks (Illustrated)


Random?

•  .NET 4.0: TPL (2010) •  .NET 4.5: async/await (2012)


Is there a better way? THERE MUST BE! THERE. MUST. BE. A. BETTER. WAY!


Warning! Mind Blowingly Different

Programming Style Ahead!


Warning! Mind Blowingly Different Programming Style Ahead!


The Actor Model


What is the actor model?


Everything is an actor.




3 Core Abilities

1.  Send messages 2. Create other actors 3. Change behavior


Messages


Actors work by passing each other messages


Message passing in action


BUZZWORD BINGO!


Example Akka.NET Message


Actors send messages to addresses


Actor addresses have location transparency


Which means…




ReactiveManifesto.org


What is Akka.NET?


Battle-Tested (JVM)


This is an actor


These are messages


Actors run on threads


Actors are lazy


Process messages one at a time


The circle of life



Hierarchies


Supervision


Switchable Behavior


And Can Form Highly Available Systems


What’s this give me?


Where can I use this? •  Analytics systems •  Marketing automation •  Multi-player games •  Device / IoT tracking •  Alerting & monitoring systems •  Recommendation engines •  Dynamic pricing •  Microservices •  Reactive UI


DEMO


hZp://LearnAkka.net


THANK YOU!

Email: [email protected]

TwiZerz: @askotzko

@AkkaDotNet


Hierarchies pt. deux


Character Actor Pattern


ActorSelection == selection by address


Actor lifecycle


Actor lifecycle

Technology

Akka.NET @ London.NET