anatomy of an elixir process and actor communication

Anatomy of an Elixir Process11/2016by Mustafa Turan

Erlang/Elixir MeetupZendesk - Dublin

What’s an Elixir Process?

Elixir Process inside BEAM

Actor Communication

Summary10 min

@mustafaturan

STATE

Mailbox

CALCULATION FUNCTIONS(MSG LISTENERS)

@mustafaturan

Elixir/Erlang ProcessAn actor

Erlang Virtual MachineOSProcess (1)

Process (2)

Process (3)

….

Process (n)

Erlang VM -- pid 109 -- pid 206 -- pid 3114 -- ...

STATE

Mailbox

CALCULATION FUNCTIONS(MSG LISTENERS)

(pid 109)

@mustafaturan

Sends a message with no-reply

Christmas sales up to %90, come to our new store and

start shopping!

(GenServer.cast)

Company A girl

@mustafaturan

Actor CommunicationBasic / one direction

Sends a messagehow r u?

Responses to messageGood! How r u?

(GenServer.call)

Mustafa Gozde

@mustafaturan

Actor CommunicationBasic / bi-directional

Sends a message

Mustafa Gozdeis unreachable!

Changed her numberor

Out of chargeor

Airplane mode

Mobile Operator

Phone number is not available

(GenServer.call)

@mustafaturan

Actor CommunicationNo process

Sends a message(GenServer.call)

Mustafa has a TTL of 1 minute! Also knows the message delivered

She did not replied in one minute!What will Mustafa do?

Mustafa GozdeSend another message?

Try to reach her from other channels / call her?

Go crazzy ????

He will behave like how you code it!@mustafaturan

Actor CommunicationTTL / bi-directional

Sends a message#1

Mustafa

Sends a message#2

Mustafa’s Message Box(1)---------------------------------------

Message #1 from Gozde

Gozde

Other girl


Message #1 from Gozde(*)Message #2 from Other Girl


Message #2 from Other Girl


*Processing not finished yet

@mustafaturan

Responses to message #1

Responses to message #2

Mustafa may change its state depending on messages.

Actor dies?What happens if the actor dies?

Sends message to its supervisor

- Down/Exit:

- Depending on strategy, supervisor decide what to do.

- Could handle its own crash by catching the ‘exit’ signal

QUESTIONS

THANKS

anatomy of an elixir process and actor communication

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