Solid Ground

Transcript

1. Solid ground @sasajuric aircloak.com

2. pattern matching OTP metaprogramming mix Distillery the pipe operator Cowboy

   Plug Phoenix Ecto functional programming community GenStage Credo ExUnit Combine Poolboy Nerves
3. None

4. LFE Erlang OTP BEAM Elixir Phoenix GenStage Ecto Plug magic

   source magic beneficiaries Cowboy Poolboy

5. long-running system many tasks soft real-time finite time program all-or-nothing

   hard real-time

6. scheduler scheduler scheduler scheduler BEAM CPU CPU CPU CPU

7. frequent context switches

8. t1 t2 t3 t4 t5 10 s 1 ms 1

   ms 1 ms 1 ms

9. t1 BEAM scheduler t2 t3 t4 t5 t1

10. t1 cooperative scheduler t2 t3 t4 t5

11. thread 1 thread n long running task long running task

    blocked cooperative scheduler …

12. thread 1 thread n long running task long running task

    BEAM scheduler … not blocked :-)

13. activities as runtime citizens

14. send(pid, :please_stop)

15. mref = Process.monitor(pid) send(pid, :please_stop) receive do {:DOWN, ^mref, :process,

    ^pid, _reason} -> :ok end

16. 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

17. 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

18. shared-nothing concurrency

19. Process heap resources

20. process-owned “stuff” is released

21. supervision tree

22. system backend frontend chat history repo cache endpoint

23. system backend chat history repo

24. supervisor foundations frequent context switching activities as runtime citizens observable

    process termination stoppable processes shared-nothing concurrency

25. syntax developer friendliness ecosystem

26. runtime 
 guarantees syntax developer friendliness ecosystem

27. Scales of Justice image taken from clipartfox.com How Erlang does

    scheduling http://jlouisramblings.blogspot.hr/2013/01/how-erlang-does-scheduling.html Erlang scheduler details https://hamidreza-s.github.io/erlang/scheduling/real-time/preemptive/migration/ 2016/02/09/erlang-scheduler-details.html The BEAM book https://github.com/happi/theBeamBook BEAM wisdoms http://beam-wisdoms.clau.se/en/latest/ Web based observer https://github.com/shinyscorpion/wobserver Recon http://ferd.github.io/recon/ Erlang performance lab http://www.erlang.pl/