title: Why is the Win32 mutex so time-consuming
body: <p>I have been reading the book of Windows via C/C++. In chapter 8, page 215, the author compared the performance of various synchronization mechanisms. And I found the poor performance of mutex. When 4 threads run simultaneously, it spent more than <strong>twenty three seconds</strong> for the mutex synchronization.</p>
  
  <p>Why is the Win32 mutex so time-consuming? And when can we use a mutex?</p>
  
  <p>PS: I posted the test code in GitHub: <a href="https://gist.github.com/985198" rel="nofollow">https://gist.github.com/985198</a></p>
  
  <p>Thanks for your replies.</p>