The document discusses Ruby's capabilities for concurrent programming. It covers how Ruby implements multithreading using fibers and EventMachine to allow for non-blocking I/O. Specifically, it discusses how EventMachine uses fibers to handle callbacks asynchronously and continually run its event loop to dispatch events, while fibers allow manually yielding execution to enable cooperative multitasking.

1. ВОЗМОЖНОСТИ RUBY
в конкурентном
программировании

3. • Обработка запроса в многопоточном сервере (Puma)
может быть очень долгим
• Как реализована многопоточность в MRI Ruby
• Как работает планировщик и приоритетность

4. • Что внутри EventMachine
• Когда вам могут понадобиться файберы
• Дальнейшее развитие многопоточности в Ruby

5. Многопоточность?
В Ruby?

6. Global Interpreter Lock
(GIL)

7. Руби, которые смогли
JRuby
Rubinius

8. MRI Ruby

9. thread.c

10. MRI
model 1: Userlevel Thread
Same as traditional ruby thread.
model 2: Native Thread with Global VM lock
Using pthread and Ruby threads run concurrent.
model 3: Native Thread with fine grain lock
Using pthread and Ruby threads run concurrent or parallel.
YARV Thread Design

11. MRI
model 1: Userlevel Thread
Same as traditional ruby thread.
model 2: Native Thread with Global VM lock
Using pthread and Ruby threads run concurrent.
model 3: Native Thread with fine grain lock
Using pthread and Ruby threads run concurrent or parallel.
YARV Thread Design

12. MRI
model 1: Userlevel Thread
Same as traditional ruby thread.
model 2: Native Thread with Global VM lock
Using pthread and Ruby threads run concurrent.
model 3: Native Thread with fine grain lock
Using pthread and Ruby threads run concurrent or parallel.
YARV Thread Design

13. Стал ли ваш код
потокобезопасным?

14. GIL нужен для защиты
внутреннего состояния MRI

15. MRI
model 1: Userlevel Thread
Same as traditional ruby thread.
model 2: Native Thread with Global VM lock
Using pthread and Ruby threads run concurrent.
model 3: Native Thread with fine grain lock
Using pthread and Ruby threads run concurrent or parallel.
YARV Thread Design

17. At Ruby Kaigi 2016, Koichi Sasada

22. immutable objects can be shared (read) across Guilds

23. Multi-VM?

24. GIL

25. Как устроен GIL?

26. 0.135
fib(29)
• Сборка вьюхи
• Обработка большого количества данных
• …

27. def show
render text: fib(29)
end
Puma, 5 потоков

28. $ (curl -i localhost:3000); (curl -i localhost:3000);
HTTP/1.1 200 OK
X-Request-Id: 839cc258-019b-4737-b169-60b05caaceca
X-Runtime: 0.139625
HTTP/1.1 200 OK
X-Request-Id: a3d85a32-53e6-4a5a-99cd-190f6f48f964
X-Runtime: 0.130910

29. $ (curl -i localhost:3000 &); (curl -i localhost:3000 &);
HTTP/1.1 200 OK
X-Request-Id: 14183c91-7e27-4f7f-be3d-d06814fa6c55
X-Runtime: 0.278702
HTTP/1.1 200 OK
X-Request-Id: 0ff1ed87-3f54-4afd-af34-218601bbafea
X-Runtime: 0.276639

30. (curl -i localhost:3000 &) x5
1) X-Runtime: 0.682356
2) X-Runtime: 0.682923
3) X-Runtime: 0.481979
4) X-Runtime: 0.412355
5) X-Runtime: 0.414157

31. Почему так?
и почему именно 0.682356

32. Thread.new { }

33. thread_timer(void *p)

34. while (system_working > 0) {
/* timer function */
ubf_wakeup_all_threads();
timer_thread_function(0);
if (TT_DEBUG) WRITE_CONST(2, "tickn");
/* wait */
timer_thread_sleep(gvl);
}

35. while (system_working > 0) {
/* timer function */
ubf_wakeup_all_threads();
timer_thread_function(0);
if (TT_DEBUG) WRITE_CONST(2, "tickn");
/* wait */
timer_thread_sleep(gvl);
}

36. while (system_working > 0) {
/* timer function */
ubf_wakeup_all_threads();
timer_thread_function(0);
if (TT_DEBUG) WRITE_CONST(2, "tickn");
/* wait */
timer_thread_sleep(gvl);
}

37. timer_thread_function(void *arg)
{
RUBY_VM_SET_TIMER_INTERRUPT(vm->running_thread);
}

38. while (system_working > 0) {
/* timer function */
ubf_wakeup_all_threads();
timer_thread_function(0);
if (TT_DEBUG) WRITE_CONST(2, "tickn");
/* wait */
timer_thread_sleep(gvl);
}

39. /* 100ms. 10ms is too small for user level thread scheduling
* on recent Linux (tested on 2.6.35)
*/
#define TIME_QUANTUM_USEC (100 * 1000)

40. Приоритетность

41. Thread 1
priority = 1 priority = 0
Thread 2
1
2
3

42. if (th->priority > 0)
limits_us <<= th->priority;
Else
limits_us >>= -th->priority;
if (th->status == THREAD_RUNNABLE)
th->running_time_us += TIME_QUANTUM_USEC;
rb_thread_schedule_limits(limits_us)

43. 100ms * 2
priority

44. rb_thread_schedule_limits(unsigned long limits_us)
{
if (th->running_time_us >= limits_us) {
/* … */
}
}

45. А что если мы хотим сами управлять потоками?

46. Fiber

47. For example, on the
* 32bit POSIX OS, ten or twenty thousands Fiber can be created.

48. • быстрое переключение (смена контекста)
• ручное управление

49. вы можете написать свой сервер
на файберах и евентмашине

50. goliath
Goliath is an open source version of the non-blocking (asynchronous)
Ruby web server framework.

51. Что такое EventMachine?
(и причем тут файберы)

52. EM.run do
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p res.response }
end

53. void EventMachine_t::Run()
{
while (RunOnce()) ;
}

54. _UpdateTime();
_RunTimers();
_AddNewDescriptors();
_ModifyDescriptors();
_RunEpollOnce();
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;

55. _UpdateTime();
_RunTimers();
_AddNewDescriptors();
_ModifyDescriptors();
_RunEpollOnce();
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;

56. _UpdateTime();
_RunTimers();
_AddNewDescriptors();
_ModifyDescriptors();
_RunEpollOnce();
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;

57. _UpdateTime();
_RunTimers();
_AddNewDescriptors();
_ModifyDescriptors();
_RunEpollOnce();
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;

58. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

59. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

60. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

61. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

62. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

63. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

64. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

65. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

66. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

67. _UpdateTime();
_RunTimers();
_AddNewDescriptors();
_ModifyDescriptors();
_RunEpollOnce();
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;

68. _UpdateTime();
_RunTimers();
_AddNewDescriptors();
_ModifyDescriptors();
_RunEpollOnce();
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;

69. _UpdateTime();
_RunTimers();
_AddNewDescriptors();
_ModifyDescriptors();
_RunEpollOnce();
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;

70. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

71. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

72. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

73. EM.run do
fiber = Fiber.new do
current_fiber = Fiber.current
p 1
res = EventMachine::HttpRequest.new("https://www.ruby-lang.org/").aget
res.callback { p 4; current_fiber.resume(5) }
p 2
puts Fiber.yield
p 6
end
p 0
fiber.resume
p 3
end

74. em-synchrony

75. Fiber
• yield
• resume

76. enumerator =
Fiber.new do
val = 0
loop do
val += 1
Fiber.yield(val)
end
end
enumerator.resume # => 1
enumerator.resume # => 2
enumerator.resume # => 3

77. Вывод

78. Спасибо
achempion