title: Python Multiprocessing program cause windows crash after 100%CPU utilization
body: <p>I am using multiprocessing pool.map for read data from csv files, process the data and write back into different format in xlsx file.
  I have 8 core processor on windows 10 machine, but I am only using 4 processes for this program, but it is still going with 100% cpu utilization as processing takes long time.<br />
  My windows 10 machine getting shut down every time the cpu utilization reaches 100 % and I am not able to execute the program fully. Can any one suggest how to avoid total 100% cpu utilization in pool.imap or prevent windows to shutdown when it occurs.</p>
  <pre><code>def _run_multiprocess(self,num_process,input_list,target_func,chunk):    
      iterator_result = None
      retVal = None
      l = mp.Lock()
      with mp.Pool(processes=(num_process),initializer=self.process_init, initargs=(l,)) as p:
          start = time.time()
          iterator_result  = p.imap(target_func, input_list,chunksize =chunk)
          p.close()
          p.join()
          end = time.time()
      return iterator_result
  </code></pre>