code dump

learning.rb

# Concurrency and Parallelism
# https://www.toptal.com/ruby/ruby-concurrency-and-parallelism-a-practical-primer

require 'benchmark'

def fib(n)
  n < 2 ? n : fib(n-1) + fib(n-2)
end  

puts Benchmark.measure { 
    100.times do |x|
     fib(30)
    end
}

# forking multi process
puts Benchmark.measure { 
    100.times do |x|
        fork do
            fib(30)
        end
    end
    Process.waitall
}

# multi threading
threads = []
puts Benchmark.measure{
  100.times do |i|
    threads << Thread.new do     
        fib(30)
    end
  end
  threads.map(&:join)
}