Async Programming & Actor Model

Transcript

1. Async Programming & Actor Model @pishen
2. Asynchronous programming val a: Future[Int] = Future { //time-consuming process result } a.map(x => x + 1) callback listener
3. Asynchronous programming val a: Future[Int] = ??? def f(x: Int): Future[Int] = ??? val r = a.map(x => f(x)) Future[Future[Int]]
4. Asynchronous programming val a: Future[Int] = ??? def f(x: Int): Future[Int] = ??? val r = a.flatMap(x => f(x)) Future[Int]
5. Asynchronous programming val a: Future[Int] = ??? def f(x: Int): Future[Int] = ??? val r = a.flatMap(x => f(x)) val p = Await.result(r, 3.seconds) Int
6. T T T T T T T Future { ??? } a.map(???) ??? Await(???)
7. T T T T T T T Future { ??? } a.map(???) F ??? Await(???)
8. T T T T T T T Future { ??? } a.map(???) F ??? Await(???)
9. T T T T T T T Future { ??? } a.map(???) F ??? F Await(???)
10. T T T T T T T Future { ??? } a.map(???) F ??? F Await(???)
11. T T T T T T Future { ??? } a.map(???) F F ??? Await(???) T
12. T T T T T T Future { ??? } a.map(???) F F ??? Await(???) T
13. T T T T T T Future { ??? } a.map(???) F F ??? Await(???) T
14. T T T T T T Future { ??? } a.map(???) F F ??? Await(???) T
15. T T T T T T Future { ??? } a.map(???) F F ??? Await(???) T
16. T T T T T T Future { ??? } a.map(???) F F ??? Await(???) T C C
17. T R
18. T R R R
19. T R R R C C C C C C C C
20. T R C C C C C C C C T T R R
21. T R C C C C C C C C T T R R R R R R R R R R R R R R 1000+
22. Orz T T R C C C C C C C T T R R R R R R R R R R R R R R 1000+ T T T T T T T T T switching thread takes time... crashed, nothing get computed after all...
23. R C C C C C C C T R R R R R R R R R R R R R R 1000+ T thread pool C T T T T T T
24. R C C C C C C C T R R R R R R R R R R R R R R T C T T T T T T access DB long computing
25. R C C C C C C C T R R R R R R R R R R R R R R T C T T T T T T access DB long computing blocking
26. R C C C C C C C T R R R R R R R R R R R R R R C T T T T T T T T T T T T T T T T T T T T T T T T T T T T T F F F F F F 1000+ async squeeze out the performance of your machine
27. Life is beautiful ...before you have states.
28. HP MP position weapon exp hunger Running Attacked Attacking Eating
29. HP MP position weapon exp hunger Running Attacked Attacking Need lock(s) to prevent strange things happen. Eating
30. HP MP position weapon exp hunger Running Attacked Attacking No matter you forward the job to DB or what. Eating
31. HP MP position weapon exp hunger Running Attacked Attacking All the other threads get blocked. Eating
32. Can we get rid of the locks?
33. P W Wrap the states in an Actor. T m h p a e mailbox
34. P W Wrap the states in an Actor. T m h p a e mailbox T
35. P W Wrap the states in an Actor. T m h p a e mailbox T
36. T T T T T T T T T T T T T T T T T front m back
37. T T T T T T T T T T T T T T T T T front m l back
38. T T T T T T T T T T T T T T T T T front m l back Disk
39. Life is beautiful ...before you have many machines.
40. T T T T T T T T T T T T T T T T T front m l back Machine A T T T T T T s Machine B Disk
41. Tell & Ask val a: ActorRef = ctx.actorOf(???) a ! “Hello!” (a ? “What’s your name?”) .mapTo[String] .map(name => ???)
42. Receive messages class MyActor extends Actor { def receive = { case “Hello!” => ??? case “What’s your name?” => sender ! “Pishen” } }
43. Create the Future[T] with Scala~