Angelina Ballerina Learns about Memory Allocation

Memory issues can be a black box often thrown over the fence for the most senior level developers to solve. For newer developers it seems like all of a sudden, your app is failing and you're seeing red everywhere. You've optimized your database queries but are still running into issues. What does this all mean? How do you figure out what's going on without solely passing it off to someone else? You'll walk away from this talk with an understanding of what memory allocation means and the tools you can use to assess what's happening.

Presented at Curry on Conf 2017 and Strange Loop 2017

Transcript

1. Angelina Ballerina Learns
   about Memory Allocation
   Allison McMillan
   @allie_p
   

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2. https://www.khanacademy.org/computing/computer-programming/programming-games-visualizations/memory-game/a/intro-to-memory
   

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3. Photo: Getty Images
   

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4. BRYAN WOOLSTON / Reuters
   MinnPost illustration by Jaime Anderson
   http://www.clotureclub.com/2013/07/22-things-most-dc-people-do/
   

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10. https://www.youtube.com/watch?v=GFfGzNXnJE8
    

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11. https://digiday.com/marketing/the-new-face-of-programmatic-efficacy-over-efficiency/
    

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13. First Seek to Understand
    - Stephen Covey
    

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14. http://www.buzinga.com.au/buzz/app-development-jargon-glossary/
    

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15. http://blackgeekygirl.deviantart.com/art/Little-Miss-Smartypants-515026930
    

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16. Definitions
    Scenarios
    Concepts
    Tools
    

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17. https://www.goodreads.com/book/show/492812.Angelina_Ballerina
    

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18. http://bookinwithbingo.blogspot.com/2011/04/
    

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19. View Slide

20. https://www.pinterest.com
    

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23. http://www.wikihow.com/Find-Your-Own-Dancing-Style
    

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24. www.pinterest.com
    

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25. https://www.pinterest.com/pin/497507090057749846/
    

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26. https://s-media-cache-ak0.pinimg.com/originals/01/69/1a/01691a66976f8e035a34990fb63e22de.jpg
    

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27. http://www.vashtie.com/culture/disneys-aladdin-still-us-dreaming-three-wishes/
    

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31. https://giphy.com/gifs/jecamartinez-ballet-ballerina-tippy-toes-yoJC2K2zjyPhKzg8lq
    

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32. http://gifsgallery.com/angelina+ballerina+gif
    

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33. https://giphy.com/gifs/loop-ballet-perfection-Ez1XmttaHzjQ4
    

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39. https://www.pinterest.com/pin/766245324070166230/
    

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40. Memory
    Can I have a box?
    

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41. +
    Memory
    

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42. Heap
    Stack
    

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43. Stack
    Clean room
    Help with
    dinner
    Do a chore
    

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44. Heap
    

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45. http://code.chaoscreated.com/
    

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46. Heap
    Turn
    Position
    Technique
    

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47. Heap
    Machine
    Heap
    Ruby
    Heap
    

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48. Heap
    Dance Heap
    Ballet
    Heap
    

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49. Heap
    Dance Heap
    Ballet Heap
    Page Page
    Page
    

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50. Heap
    Machine Heap
    Ruby Heap
    Page
    Node/Slot
    Ruby Object
    

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51. Heap
    Dance Heap
    Ballet Heap
    Feet Positions
    Node/Slot
    First
    position
    Node/Slot
    Fourth
    position
    https://dancer.com/ballet-info/in-the-studio/terms-positions/
    

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52. Open slot
    

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53. new first open slot
    Bump Pointer Allocation
    

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54. Eden page
    Retained objects
    

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55. http://artandpractice.blogspot.nl/2013/04/huma-1315-chapter-8-dance.html
    new
    memory
    

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59. Garbage collection is a type of
    automatic memory
    management that makes a
    program seem like it has
    infinite memory by reclaiming
    objects that are no longer in
    use.
    

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60. www.youtube.com
    

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61. https://alchetron.com/John-McCarthy-(computer-scientist)-1012892-W
    

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62. http://imgur.com/gallery/btPUV
    

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63. https://giphy.com/gifs/cheezburger-funny-amazing-76D0WNoMfMOyc
    

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64. https://en.wikipedia.org/wiki/Box_Step
    

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65. http://makeagif.com/gif/stanford-viennese-ball-2013-opening-committee-waltz-cH-YJy
    

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66. Heap
    

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67. Heap
    

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68. Heap
    

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69. Object Graph
    Heap
    object
    Root
    References
    References
    Heap
    object
    Heap
    object
    

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70. http://classicalballetnews.com/how-to-releve-in-ballet-video/how-to-releve-in-ballet/
    

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71. Stack
    Clean room
    Help with
    dinner
    Do a chore
    Angelina, Clean your room
    

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72. Ballet Heap
    Page
    

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73. https://www.tumblr.com/search/ballet%20perfection
    

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74. Granule
    Chunk
    Lists
    

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75. Slot
    Slot
    Slot
    Slot
    

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76. Slot
    Slot
    Slot
    Slot
    r value
    

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77. https://speakerdeck.com/pat_shaughnessy/visualizing-garbage-collection-in-rubinius-jruby-and-ruby-2-dot-0
    

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78. “first position”
    class: Position
    Object: position1 = Position.new
    

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79. Object: position1 = Position.new Address
    

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81. Program Footprint
    

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82. https://www.pinterest.com
    

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83. Object
    Space
    

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84. Mutator
    Collector
    

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85. https://hirshhorn.si.edu/kusama/infinity-rooms/
    

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86. http://gifrific.com/baby-groot-dancing-guardians-of-the-galaxy/
    

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87. http://www.blu-ray.com/movies/screenshot.php?movieid=44938&position=5
    

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88. Root
    

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89. https://www.gutenberg.org/files/27367/27367-h/27367-h.htm
    Root
    

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90. Root
    

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91. https://www.americandancesportcenter.com/waltz
    

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92. http://tech.eu/features/2921/enevo-waste-management-profile/
    

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93. Root
    

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94. 1 1
    1
    1
    1
    0 0
    0
    

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95. 1 1
    1
    1
    1
    0 0
    0
    

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96. https://pixabay.com/en/playmobil-toy-garbage-collector-771313/
    

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97. FromSpace
    ToSpace
    

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98. FromSpace
    ToSpace
    

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99. Pointer
    FromSpace
    ToSpace
    

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100. FromSpace (formerly ToSpace)
     ToSpace
     

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101. FromSpace
     

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102. Mark
     Sweep
     Compact
     

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103. Root
     

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104. Root
     

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105. Root
     

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106. Root
     

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107. Root
     

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108. Root
     

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109. https://giphy.com/gifs/dance-black-and-white-dancing-FobM3MLsUVmnu
     

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110. https://dribbble.com/shots/3588547-Hiplet-Desigual-2
     

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111. Generation 0
     Generation 1
     Root
     

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112. Generation 0
     Root
     

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113. Generation 0
     Root
     

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114. Generation 0
     Root
     

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115. Generation 1
     Root
     

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116. Generation 1
     Generation 0
     Root
     

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117. Generation 1
     Generation 0
     Root
     

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118. Generation 1
     Generation 0
     Root
     

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119. Generation 1
     Generation 0
     Root
     

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120. Write barrier
     Generation 1
     Generation 0
     Root
     

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121. Generation 1
     Generation 0
     Root
     

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122. Dancing with the stars
     

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123. https://coderwall.com/p/yutdhq/understanding-garbage-collection-p1-2
     

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124. Root
     

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125. Root
     

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126. https://giphy.com/gifs/agentm-agent-m-Xdcj75alQutVe
     

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127. writer barrier
     Root
     

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128. https://www.pinterest.com/pin/470626229787955295/
     

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132. https://i2.wp.com/sassandbalderdash.com/wp-content/uploads/2014/03/letitgo7.gif
     

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133. Rails
     Apps
     Retained
     Memory
     Allocated
     Memory
     = +
     

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135. http://www.pastposters.com/details.php?prodId=4009
     

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136. 2.3.1 :001 >
     GC.stat(:total_freed_objects)
     => 97198
     

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137. http://gifrific.com/uga-mens-swim-and-dive-team-harlem-shake-dance/
     

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138. {

     :count=>0,

     :heap_allocated_pages=>24,

     :heap_sorted_length=>24,

     :heap_allocatable_pages=>0,

     :heap_available_slots=>9783,

     :heap_live_slots=>7713,

     :heap_free_slots=>2070,

     :heap_final_slots=>0,

     :heap_marked_slots=>0,

     :heap_swept_slots=>0,

     :heap_eden_pages=>24,

     :heap_tomb_pages=>0,

     :total_allocated_pages=>24,

     :total_freed_pages=>0,

     :total_allocated_objects=>7796,

     :total_freed_objects=>83,

     :malloc_increase_bytes=>2389312,

     :malloc_increase_bytes_limit=>16777216,

     :minor_gc_count=>0,

     :major_gc_count=>0,

     :remembered_wb_unprotected_objects=>0,

     :remembered_wb_unprotected_objects_limit=>0,

     :old_objects=>0,

     :old_objects_limit=>0,

     :oldmalloc_increase_bytes=>2389760,

     :oldmalloc_increase_bytes_limit=>16777216

     }
     

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139. Heap Allocated Pages
     Pages
     

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140. Heap Sorted Length
     Slots
     

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141. Heap available slots
     Slots
     

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142. Heap live slots
     

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143. Heap Free Slots
     

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144. Heap Final Slots
     Root
     

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145. Total Allocated Objects
     Root
     

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146. Total Freed Objects
     Root
     

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147. 2.3.1 :001 >
     GC.stat[:count]
     

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148. GC::Profiler.enable
     10000.times do
     puts “angelina turns”
     end
     GC.start
     puts GC::Profiler.result
     GC::Profiler.disable
     

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149. Index 1
     Invoke Time(sec) 0.075
     Use Size(byte) 584120
     Total Size(byte) 1207680
     Total Object 30192
     GC Time(ms)
     1.91500000000000003553
     

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150. > ObjectSpace.each_object
     

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151. Object
     Space
     

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152. 2.3.1 :003 > ObjectSpace.count_objects
     =>
     {:TOTAL=>53805, :FREE=>7063, :T_OBJECT=>11
     10, :T_CLASS=>919, :T_MODULE=>42, :T_FLOAT
     =>4, :T_STRING=>28307, :T_REGEXP=>195, :T_
     ARRAY=>5470, :T_HASH=>180, :T_STRUCT=>3, :
     T_BIGNUM=>2, :T_FILE=>12, :T_DATA=>269, :T
     _MATCH=>130, :T_COMPLEX=>1, :T_SYMBOL=>7,
     :T_IMEMO=>5201, :T_NODE=>4842, :T_ICLASS=>
     48}
     

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153. Derailed Benchmarks
     Memory_profiler
     Rack-mini-profiler
     get_process_mem
     

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154. http://harlequinblog.com/2016/08/11-signs-youre-a-book-lover-and-should-be-celebrating-national-book-lovers-day/
     

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155. https://www.emaze.com/@AWZCLQTQ/Rube-Goldberg-Machine
     

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156. Resources
     http://daydreamsinruby.com/
     memory-resources/
     

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157. Thank you
     

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158. @allie_p
     allison.p.mcmillan@gmail.com
     www.collectiveidea.com
     www.daydreamsinruby.com
     

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