Server-side Kotlin with Coroutines

on YouTube ↗51m

" summary

Kotlin coroutines replace thousands of blocking threads with a few event threads plus tiny continuations so servers scale by default and require sizing roughly to CPU cores for CPU work and to I/O threads for sockets. Suspend functions compile to callback-style continuations (one small object per suspension), integrate with Reactor/CompletableFuture or Spring 5.2, and use dispatchers to isolate blocking or CPU work. suspend functions enable low-allocation async, structured concurrency prevents leaking child tasks. Flow replaces channels for cold, cancelable streams.

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" chapters (33)

1. 0:00Introduction
2. 1:51Old-school client-server monolith
3. 2:32Sizing threads - easy
4. 4:08Complex business logic
5. 5:22What if a service is slow?
6. 5:40Blocks threads
7. 7:43Release the thread
8. 10:47Suspend behind the scenes
9. 11:42Performance!
10. 13:43Integration
11. 14:44Release thread?
12. 14:58Blocking server
13. 15:50Asynchronous server
14. 16:40Server integrated with coroutines
15. 17:30Server not integrated with coroutines
16. 19:23Suspend is efficient
17. 21:14Let's go deeper (with coroutines)
18. 21:49Call stack with coroutines
19. 23:26Thread pools
20. 27:51CPU-bound code
21. 28:14Fine-grained control and encapsulation
22. 33:14Concurrency with async (futures)
23. 35:25Concurrency with coroutines
24. 38:04Without coroutine scope?
25. 38:54Convention
26. 39:41Types as documentation
27. 40:35Types are enforced
28. 42:46Green threads / Fibers
29. 43:25Fibers promise
30. 44:40Solution - shared thread pool
31. 45:54Returning many responses
32. 48:02Where's the catch?
33. 50:14Flow example

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