Solid Ground

ElixirDaze 2017

Video available at https://www.youtube.com/watch?v=5SbWapbXhKo

Transcript

1. Solid ground @sasajuric aircloak.com
3. long-running system many tasks soft real-time finite time program all-or-nothing hard real-time
4. NIFs
5. scheduler scheduler scheduler scheduler BEAM CPU CPU CPU CPU
6. frequent context switches
7. t1 t2 t3 t4 t5 10 s 1 ms 1 ms 1 ms 1 ms
8. t1 t2 t3 t4 t5 t1 BEAM scheduler
9. t2 t3 t4 t5 t1 cooperative scheduler
10. thread 1 thread n … long running task long running task blocked cooperative scheduler
11. thread 1 thread n … long running task long running task not blocked :-) BEAM scheduler
12. activities as runtime citizens
13. send(pid, :please_stop)
14. mref = Process.monitor(pid) send(pid, :please_stop) receive do {:DOWN, ^mref, :process, ^pid, _reason} -> :ok end
15. mref = Process.monitor(pid) send(pid, :please_stop) receive do {:DOWN, ^mref, :process, ^pid, _reason} -> :ok after :timer.seconds(5) -> Process.exit(pid, :kill) receive do {:DOWN, ^mref, :process, ^pid, _reason} -> :ok end end
16. task = Task.async(fn -> ... end) case Task.yield(task, :timer.seconds(5)) do {:ok, result} -> do_something(result) nil -> Task.shutdown(task, :brutal_kill) end
17. shared-nothing concurrency
18. Process heap resources
19. process-owned “stuff” is released
20. supervision tree
21. system backend frontend chat history repo cache endpoint
22. system backend chat history repo
23. supervisor foundations frequent context switching activities as runtime citizens observable process termination stoppable processes shared-nothing concurrency
24. runtime 
 guarantees syntax developer friendliness ecosystem
25. Image credit Scales of Justice