title: Multiprocessing pool in python took more time
body: <p>So, I started learning multiprocessing in python. I created a pool for function 'res'. I was interested in time after run program using the pool and using normal way, I thought that if I use pool processing time would be reduced but as I see, pool took  10.0413179397583 sec(s) and normal way took 0.005002737045288086 sec(s). What did I miss? </p>
  
  <pre><code>import multiprocessing as mp
  import time
  
  def res(a):
      squ = 0
      for i in range(a):
          squ += i**2
      return squ
  
  if __name__ == "__main__":
  
      t1 = time.time()
      p = mp.Pool()
      result = p.map(res, range(10000))
      p.close()
      p.join()
      print(time.time()-t1)
  
      t2 = time.time()
      result = []
      sum = 0
      for i in range(10000):
          sum += i**2
          result.append(sum)
      print(time.time()-t2)
  </code></pre>