title: Is memory allocation a system call?
body: <p>Is memory allocation a system call? For example, <code>malloc</code> and <code>new</code>. Is the heap shared by different processes and managed by the OS. What about private heap? If memory allocation in the heap is managed by the OS, how expensive is this? </p>
  
  <p>I would also like to have some link to places where I can read more about this topic.</p>