Event-driven programming for the masses (WebMeetupCgn)

What makes nginx faster than Apache's original design? What makes Node.js applications faster than traditional web applications? How can we achieve the same benefits for our own applications? This talk discusses how event-driven programming can help in building high performance, non-blocking, reactive, concurrent, single-threaded applications (bingo). Don't worry, no need to install Node.js and npm install half the internet. Let's build high-performance applications from scratch with whatever language you're most comfortable with!

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This talk was presented at WebMeetupCgn (https://www.meetup.com/de-DE/Web-Meetup-Cologne/events/255796092/) as one of two talks this day (~30 min each). This implies that this is only supposed to be a 101 introduction. The talk includes a number of live demos and examples which are not included as part of the slides, so you may be missing some context here. See you at the next event perhaps?

Transcript

1. event-driven programming
   for the masses
   High performance for fun and profit.
   

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2. Agenda
   - Hello!
   - 101 of event-driven programming
   - Examples from scratch
   - Putting into practice
   - Conclusions
   2
   

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3. Hello!
   3
   

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4. $ whoami
   4
   

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5. $ whoami
   Christian Lück
   5
   

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6. $ whoami
   Christian Lück
   6
   

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7. $ whoami
   Christian Lueck
   7
   

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8. $ whoami
   Christian Lueck
   8
   

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9. $ whoami
   Christian Lueck
   @clue
   9
   

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10. $ whoami
    Christian Lueck
    @another_clue
    10
    

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11. $ whoami
    Christian Lueck
    @another_clue
    passionate about pushing the limits
    11
    

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12. $ whoami
    Christian Lueck
    @another_clue
    passionate about pushing the limits
    freelance software engineer 12
    

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13. Who are you?
    13
    now that you know me…
    

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14. Who are you?
    14
    now that you know me…
    - programmers / developers?
    - architects / engineers?
    

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15. What is event-driven programming?
    15
    

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16. What is an event?
    16
    

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17. event
    17
    

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18. event
    18
    past action recognized by environment
    

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19. event
    19
    past action recognized by environment
    triggered reaction, listening
    

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20. event
    20
    past action recognized by environment
    triggered reaction, listening
    hardware or software
    

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21. event-driven
    21
    

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22. event-driven
    program flow driven by events
    22
    

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23. event-driven
    program flow driven by events
    react to events (handler)
    23
    

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24. event-driven
    program flow driven by events
    react to events (handler)
    event-loop (reactor)
    24
    

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25. event-driven programming
    25
    

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26. event-driven program?
    26
    

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27. event-driven web applications
    27
    

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28. frontend
    28
    backend
    

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29. frontend
    29
    

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30. frontend
    mouse clicks, keyboard input (UI)
    30
    

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31. frontend
    mouse clicks, keyboard input (UI)
    backend communication
    31
    

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32. frontend
    mouse clicks, keyboard input (UI)
    backend communication
    browser APIs
    32
    

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33. backend
    33
    

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34. backend
    network protocols (HTTP)
    34
    

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35. backend
    network protocols (HTTP)
    database APIs
    35
    

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36. backend
    network protocols (HTTP)
    database APIs
    filesystem
    36
    

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37. backend is all about I/O
    37
    

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38. is your backend all about I/O?
    38
    

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39. Show me some code!
    39
    

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40. Show me some code!
    Programming language?
    40
    

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41. Node.js
    41
    

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42. Node.js
    42
    good fit, huge ecosystem
    

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43. Node.js
    43
    good fit, huge ecosystem
    did not invent concept
    

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44. Node.js
    44
    good fit, huge ecosystem
    did not invent concept
    npm install…
    

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45. nodejs?
    45
    

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46. no js!
    46
    

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47. Everybody’s favorite language…
    47
    

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48. PHP
    48
    

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49. PHP
    49
    gets the job done
    

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50. PHP
    50
    gets the job done
    widespread usage
    

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51. PHP
    51
    gets the job done
    widespread usage
    if PHP can do it…
    

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52. Examples and demo time
    52
    

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53. Putting into practice
    53
    

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54. Knowing concepts
    is good!
    54
    Building from
    scratch is not!
    

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55. event-driven programming can get complex
    55
    

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56. event-driven programming can get complex
    use abstractions!
    56
    

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57. View Slide

58. View Slide

59. 59
    related
    

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60. 60
    related
    event-driven
    

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61. 61
    related
    event-driven
    asynchronous
    

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62. 62
    related
    event-driven
    asynchronous
    multi-threaded
    

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63. core concept
    63
    

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64. core concept
    often intertwined
    64
    

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65. event-driven, non-blocking I/O
    for the masses?
    65
    

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66. timers
    66
    

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67. sockets
    67
    

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68. HTTP
    68
    

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69. nginx vs.
    Apache
    69
    

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70. Node.js vs.
    PHP-FPM
    70
    

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71. ? requests/s
    71
    

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72. 5k requests/s
    72
    this is a local single core benchmark!
    dual core i3 => 10k requests/s
    36M requests/h
    

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73. instant real-time updates
    73
    

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74. live updates
    WebSockets
    74
    

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75. background worker queues
    75
    

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76. no polling
    76
    jobs instantly picked up
    thousands of jobs per second
    concurrently processing hundreds or more
    

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77. 700 MiB/s
    77
    dockerd maxed out
    PHP not
    

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78. databases
    78
    

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79. 50k OP/s
    pure PHP
    who needs native code anyway?
    79
    

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80. event-driven, non-blocking I/O is
    massively fast
    80
    

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81. for the masses?
    81
    

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82. when?
    82
    

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83. when?
    83
    app is I/O bound
    

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84. when?
    84
    app is I/O bound
    high(er) performance is wanted
    

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85. when?
    85
    app is I/O bound
    high(er) performance is wanted
    blocking and non-blocking can be separated
    

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86. event-driven, non-blocking I/O is
    massively useful
    86
    

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87. Conclusions
    87
    

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88. event-driven
    88
    

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89. event-driven
    89
    basic paradigm
    

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90. event-driven
    90
    basic paradigm
    very fast & versatile
    

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91. event-driven
    91
    basic paradigm
    very fast & versatile
    consider when app is I/O bound
    

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92. integration
    92
    

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93. integration
    non-blocking and blocking don’t mix well
    93
    

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94. integration
    non-blocking and blocking don’t mix well
    decide for either approach
    94
    

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95. integration
    non-blocking and blocking don’t mix well
    decide for either approach
    isolate & communicate
    95
    

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96. ReactPHP
    96
    

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97. ReactPHP
    97
    a real deal and here to stay
    

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98. ReactPHP
    98
    a real deal and here to stay
    stable & production ready
    

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99. ReactPHP
    99
    a real deal and here to stay
    stable & production ready
    *awesome*
    

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100. // thank you!
     $loop->stop();
     100
     @another_clue – https://lueck.tv/
     

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