Elixir – Peeking into Elixir's Processes, OTP and Supervisors
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The document discusses key concepts in Elixir including processes, OTP framework, and supervisors. It provides an overview of processes as Elixir's basic concurrency primitive. It then explains OTP as a framework for building fault-tolerant and scalable applications, including behaviors like GenServer and common patterns. Finally, it covers supervisors and how they provide fault tolerance and recovery through restarting processes based on different strategies. Code examples are provided to demonstrate processes, GenServers, and supervisors.
Elixir – Peeking into Elixir's Processes, OTP and Supervisors
- 1. ElixirPeeking into Elixir’s Processes, OTP & Supervisors 21st March 2014 /benjamintanweihao /bentanweihao [email protected]
- 2. What will we learn today? Elixir & Erlang In less than 5 minutes
- 3. Elixir & Erlang In less than 5 minutes Processes 101 The Basic Concurrency Primitive What will we learn today?
- 4. Elixir & Erlang In less than 5 minutes OTP Framework and much more Processes 101 The Basic Concurrency Primitive What will we learn today?
- 5. Elixir & Erlang In less than 5 minutes OTP Framework and much more Supervisors Fault Tolerance & Recovery Processes 101 The Basic Concurrency Primitive What will we learn today?
- 7. Elixir & ErlangIn less than 5 minutes
- 8. Ohai, Erlang! Erlang is a general-purpose concurrent, garbage-collected programming language and runtime system. The sequential subset of Erlang is a functional language, with eager evaluation, single assignment, and dynamic typing. It was designed by Ericsson to support distributed, fault-tolerant, soft-real-time, non- stop applications. It supports hot swapping, so that code can be changed without stopping a system.
- 9. Ohai, Erlang! Erlang is a general-purpose concurrent, garbage-collected programming language and runtime system. The sequential subset of Erlang is a functional language, with eager evaluation, single assignment, and dynamic typing. It was designed by Ericsson to support distributed, fault-tolerant, soft-real-time, non- stop applications. It supports hot swapping, so that code can be changed without stopping a system.
- 10. • Free lunch is over Why Elixir ?
- 11. Why Elixir ? • Free lunch is over • Hyper-threading & Multicore • Faster software means using all cores! • But … Concurrency -> Coordination • Functional makes this easier
- 12. Design Goals of Elixir 1.Productivity 2.Extensibility 3.Compatibility
- 16. Extensibility Macros & Meta-programming Implementing unless using if
- 17. Extensibility Macros & Meta-programming Implementing unless using if
- 18. Compatibility Elixir can call Erlang code, without any conversion cost at all.
- 19. Compatibility Elixir can use Erlang libraries!
- 20. The Actor Concurrency Model • Actor = Process
- 21. The Actor Concurrency Model • Actor = Process • A process performs a specific task when it receives a message
- 22. The Actor Concurrency Model • Actor = Process • A process performs a specific task when it receives a message • In turn, the process can reply to the sender
- 23. The Actor Concurrency Model • Actor = Process • A process performs a specific task when it receives a message • In turn, the process can reply to the sender • All messages go to a processes’ mailbox – Q of unprocessed messages sent from other processes that are not yet consumed
- 24. The Actor Concurrency Model • Actor = Process • A process performs a specific task when it receives a message • In turn, the process can reply to the sender • All messages go to a processes’ mailbox – Q of unprocessed messages sent from other processes that are not yet consumed Shared-nothing Async Message-passing
- 25. Processes 101The Basic Concurrency Primitive
- 26. Creating Processes & Sending Messages in Elixir Creating a Process
- 27. Creating Processes & Sending Messages in Elixir Module, Function, Arguments
- 28. Creating Processes & Sending Messages in Elixir Process id
- 29. Creating Processes & Sending Messages in Elixir Sending a Message to w1
- 30. Creating Processes & Sending Messages in Elixir Process waits for a message …
- 31. Creating Processes & Sending Messages in Elixir Pattern matches!
- 32. Creating Processes & Sending Messages in Elixir Result is sent back to the calling process (self)
- 33. Creating Processes & Sending Messages in Elixir Returns immediately
- 34. Creating Processes & Sending Messages in Elixir Get result from self
- 35. Creating Processes & Sending Messages in Elixir Demo
- 36. OTPFramework and much more
- 37. What is OTP? • Comes with Elixir/Erlang • Framework to build applications that are fault- tolerant, scalable, distributed • Databases + Profilers + Debuggers
- 38. OTP Behaviours • GenServer • Supervisor • Application
- 39. An Example GenServer Implement the GenServer Behaviour
- 40. An Example GenServer Implement GenServer Callbacks
- 41. An Example GenServer Callbacks are NOT called explicitly
- 42. An Example GenServer OTP calls the callbacks.
- 43. An Example GenServer Synchronous Call: Caller waits for reply
- 44. An Example GenServer Asynchronous Call: Caller doesn’t wait for reply
- 45. An Example GenServer Demo
- 46. SupervisorsFault Tolerance & Recovery
- 47. Supervisors for Fault Tolerance and Recovery one_for_one restart strategy
- 48. Supervisors for Fault Tolerance and Recovery rest_for_all restart strategy
- 49. Supervisors for Fault Tolerance and Recovery rest_for_one restart strategy
- 50. An Example Supervisor Implement the Supervisor Behaviour
- 51. An Example Supervisor Declaring the Supervision tree. Both Supervisors and Workers (e.g. GenServers) can be supervised.
- 53. An Example Supervisor Declare the restart strategy
- 54. Supervisor Demo Supervisor A Supervisor B Supervisor C Supervisor D Server D Server B Worker 1Worker 1Worker
- 55. Supervisor Demo Supervisor A Supervisor B Supervisor C Supervisor D Server D Server B Worker 1Worker 1Worker one_for_one
- 56. Supervisor Demo Supervisor A Supervisor B Supervisor C Supervisor D Server D Server B Worker 1Worker 1Worker one_for_all
- 57. Supervisor Demo Supervisor A Supervisor B Supervisor C Supervisor D Server D Server B Worker 1Worker 1Worker simple_one_for_one
- 58. Supervisor Demo Supervisor A Supervisor B Supervisor C Supervisor D Server D Server B Worker 1Worker 1Worker one_for_one
- 59. Supervisor Demo Supervisor A Supervisor B Supervisor C Supervisor D Server D Server B Worker 1Worker 1Worker one_for_one simple_one_for_one one_for_all one_for_one
- 60. Elixir & Erlang In less than 5 minutes OTP Framework and much more Supervisors Fault Tolerance & Recovery Processes 101 The Basic Concurrency Primitive
- 61. Resources
- 62. Work in Progress! ! Sign up at: http://www.exotpbook.com Me.