kek

proc_val = nil

report = MemoryProfiler.report do
  # A method that creates and returns a Proc.
  # It also uses a lot of memory before doing so
  def create_proc
    # Create an array with 10 million numbers  
    large_array = Array.new(10000000, 0)  
    # Use the array to do something useful  
    # ...  
    # Reset when done  
    large_array = nil 
    # Create and return Proc
    message = 'Hello World!'  
    Proc.new { puts message }  
  end  
  proc_val = create_proc
end  

report.pretty_print
# Output:
# Total allocated: 80000280 bytes (4 objects)
# Total retained:  240 bytes (3 objects)

allocated memory by gem
-----------------------------------
  80000280  other

allocated memory by file
-----------------------------------
  80000280  (pry)

allocated memory by location
-----------------------------------
  80000040  (pry):19
       200  (pry):24
        40  (pry):23

allocated memory by class
-----------------------------------
  80000040  Array
       120  RubyVM::Env
        80  Proc
        40  String

allocated objects by gem
-----------------------------------
         4  other

allocated objects by file
-----------------------------------
         4  (pry)

allocated objects by location
-----------------------------------
         2  (pry):24
         1  (pry):19
         1  (pry):23

allocated objects by class
-----------------------------------
         1  Array
         1  Proc
         1  RubyVM::Env
         1  String

retained memory by gem
-----------------------------------
  80000280  other

retained memory by file
-----------------------------------
  80000280  (pry)

retained memory by location
-----------------------------------
  80000040  (pry):19
       200  (pry):24
        40  (pry):23

retained memory by class
-----------------------------------
  80000040  Array
       120  RubyVM::Env
        80  Proc
        40  String

retained objects by gem
-----------------------------------
         4  other

retained objects by file
-----------------------------------
         4  (pry)

retained objects by location
-----------------------------------
         2  (pry):24
         1  (pry):19
         1  (pry):23

retained objects by class
-----------------------------------
         1  Array
         1  Proc
         1  RubyVM::Env
         1  String


Allocated String Report
-----------------------------------
         1  "Hello World!"
         1  (pry):23


Retained String Report
-----------------------------------
         1  "Hello World!"
         1  (pry):23

=> nil
[7] pry(main)> exit
rapide-macbook:BankToTheFuture rapide$ rails c
Running via Spring preloader in process 98250
Loading development environment (Rails 4.1.16)
[1] pry(main)> proc_val1 = nil
=> nil
[2] pry(main)> proc_val2 = nil
=> nil
[3] pry(main)> require 'memory_profiler'
=> true
[4] pry(main)> report = MemoryProfiler.report do
[4] pry(main)*   def create_proc
[4] pry(main)*     # Create an array with 10 million numbers  
[4] pry(main)*     large_array = Array.new(10000000, 0)  
[4] pry(main)*     # Use the array to do something useful  
[4] pry(main)*     # ...  
[4] pry(main)*     # Create and return Proc
[4] pry(main)*     message = 'Hello World!'  
[4] pry(main)*     Proc.new { puts message }  
[4] pry(main)*   end  
[4] pry(main)*   proc_val1 = create_proc
[4] pry(main)*   # dupa
[4] pry(main)*   # dupa
[4] pry(main)*   proc_val2 = create_proc
[4] pry(main)* end  
=> #<MemoryProfiler::Results:0x3ffcca411610>
[5] pry(main)> report.pretty_print
Total allocated: 160000560 bytes (8 objects)
Total retained:  160000560 bytes (8 objects)

allocated memory by gem
-----------------------------------
 160000560  other

allocated memory by file
-----------------------------------
 160000560  (pry)

allocated memory by location
-----------------------------------
 160000080  (pry):7
       400  (pry):12
        80  (pry):11

allocated memory by class
-----------------------------------
 160000080  Array
       240  RubyVM::Env
       160  Proc
        80  String

allocated objects by gem
-----------------------------------
         8  other

allocated objects by file
-----------------------------------
         8  (pry)

allocated objects by location
-----------------------------------
         4  (pry):12
         2  (pry):11
         2  (pry):7

allocated objects by class
-----------------------------------
         2  Array
         2  Proc
         2  RubyVM::Env
         2  String

retained memory by gem
-----------------------------------
 160000560  other

retained memory by file
-----------------------------------
 160000560  (pry)

retained memory by location
-----------------------------------
 160000080  (pry):7
       400  (pry):12
        80  (pry):11

retained memory by class
-----------------------------------
 160000080  Array
       240  RubyVM::Env
       160  Proc
        80  String

retained objects by gem
-----------------------------------
         8  other

retained objects by file
-----------------------------------
         8  (pry)

retained objects by location
-----------------------------------
         4  (pry):12
         2  (pry):11
         2  (pry):7

retained objects by class
-----------------------------------
         2  Array
         2  Proc
         2  RubyVM::Env
         2  String


Allocated String Report
-----------------------------------
         2  "Hello World!"
         2  (pry):11


Retained String Report
-----------------------------------
         2  "Hello World!"
         2  (pry):11

=> nil
[6] pry(main)> exit
rapide-macbook:BankToTheFuture rapide$ rails c
Running via Spring preloader in process 98291
Loading development environment (Rails 4.1.16)
[1] pry(main)> proc_val = nil
=> nil
[2] pry(main)> report = MemoryProfiler.report do
[2] pry(main)*   def create_proc
[2] pry(main)*     # Create an array with 10 million numbers  
[2] pry(main)*     large_array = Array.new(10000000, 0)  
[2] pry(main)*     # Use the array to do something useful  
[2] pry(main)*     # ...  
[2] pry(main)*     # Reset when done  
[2] pry(main)*     large_array = nil  
[2] pry(main)*     
[2] pry(main)*     # Create and return Proc  
[2] pry(main)*     message = 'Hello World!'  
[2] pry(main)*     Proc.new { puts message }  
[2] pry(main)*   end  
[2] pry(main)*   proc_val = create_array
[2] pry(main)* end  
NameError: uninitialized constant MemoryProfiler
from (pry):2:in `<main>'
[3] pry(main)> report = MemoryProfiler.report do
[3] pry(main)*   def create_proc
[3] pry(main)*     # Create an array with 10 million numbers  
[3] pry(main)*     large_array = Array.new(10000000, 0)  
[3] pry(main)*     # Use the array to do something useful  
[3] pry(main)*     # ...  
[3] pry(main)*     # Reset when done  
[3] pry(main)*     large_array = nil  
[3] pry(main)*     
[3] pry(main)*     # Create and return Proc  
[3] pry(main)*     message = 'Hello World!'  
[3] pry(main)*     Proc.new { puts message }  
[3] pry(main)*   end  
[3] pry(main)*   proc_val = create_proc
[3] pry(main)* end  
NameError: uninitialized constant MemoryProfiler
from (pry):17:in `<main>'
[4] pry(main)> require 'memory_profiler'
=> true
[5] pry(main)> report = MemoryProfiler.report do
[5] pry(main)*   def create_proc
[5] pry(main)*     # Create an array with 10 million numbers  
[5] pry(main)*     large_array = Array.new(10000000, 0)  
[5] pry(main)*     # Use the array to do something useful  
[5] pry(main)*     # ...  
[5] pry(main)*     # Reset when done  
[5] pry(main)*     large_array = nil  
[5] pry(main)*     
[5] pry(main)*     # Create and return Proc  
[5] pry(main)*     message = 'Hello World!'  
[5] pry(main)*     Proc.new { puts message }  
[5] pry(main)*   end  
[5] pry(main)*   proc_val = create_proc
[5] pry(main)* end  
=> #<MemoryProfiler::Results:0x3ffcca411610>
[6] pry(main)> report.pretty_print
Total allocated: 80000280 bytes (4 objects)
Total retained:  240 bytes (3 objects)

allocated memory by gem
-----------------------------------
  80000280  other

allocated memory by file
-----------------------------------
  80000280  (pry)

allocated memory by location
-----------------------------------
  80000040  (pry):36
       200  (pry):44
        40  (pry):43

allocated memory by class
-----------------------------------
  80000040  Array
       120  RubyVM::Env
        80  Proc
        40  String

allocated objects by gem
-----------------------------------
         4  other

allocated objects by file
-----------------------------------
         4  (pry)

allocated objects by location
-----------------------------------
         2  (pry):44
         1  (pry):36
         1  (pry):43

allocated objects by class
-----------------------------------
         1  Array
         1  Proc
         1  RubyVM::Env
         1  String

retained memory by gem
-----------------------------------
       240  other

retained memory by file
-----------------------------------
       240  (pry)

retained memory by location
-----------------------------------
       200  (pry):44
        40  (pry):43

retained memory by class
-----------------------------------
       120  RubyVM::Env
        80  Proc
        40  String

retained objects by gem
-----------------------------------
         3  other

retained objects by file
-----------------------------------
         3  (pry)

retained objects by location
-----------------------------------
         2  (pry):44
         1  (pry):43

retained objects by class
-----------------------------------
         1  Proc
         1  RubyVM::Env
         1  String


Allocated String Report
-----------------------------------
         1  "Hello World!"
         1  (pry):43


Retained String Report
-----------------------------------
         1  "Hello World!"
         1  (pry):43

=> nil