gistfile1.txt

#!/usr/bin/env ruby
 
def mem_usage
  `ps -o rss= -p #{$$}`.to_i
end
 
@count = (ARGV[0] || 5).to_i

puts "current process id is #{$$}" 
puts "Memory before anything: #{mem_usage}"

@array_a = []
@array_b = []
1000000.times { |n| @array_a << n}
500000.times { |n| @array_b << n}

def a
  b
end

def b
  c
end

def c
  d
end

def d
  e
end

def e
  @count.times do |n|
    puts "Memory before process number #{n}: #{mem_usage}"
    @array_a - @array_b
    puts "Memory after process number #{n}: #{mem_usage}"
  end
end

puts "Memory before process: #{mem_usage}"

a

@array_a = nil
@array_b = nil
GC.start
puts "Memory on complete: #{mem_usage}"