distsys-dec-11.md

Elixir - DistSys Lecture - Dec 11th, 2018

Actor Model

• ID

• stack

• msg queue (incoming)

• Two actors have no shared memory

One of the actors has a counter. I want other actors to be able to increment the counter and be able to get the value of the counter

We’ll make two messages: { QUERY : my_pid; } { INCREMENT }

Elixir

send self(), {:TEST} # send message

# how to receieve messages
# receive blocks until it receives the message
receive do
	{:TEST} -> IO.puts("Got it!")
	# after receiving, the message is deleted from the message
	# queue
end

Node 1

# Name the current process so others can communicate with it
Process.register self(), :bestprocess

receive do {:TEST, x} -> IO.puts(x) end

Node 2

# send a message to the "bestprocess" process on the node
# "foo@tenger"
send {:bestprocess, :"foo@tenger"}, {:TEST, "barf"}