title: How much memory could vm use
body: <p>I read the document <a href="http://www.redhat.com/magazine/001nov04/features/vm/" rel="noreferrer"><strong>Understanding Virtual Memory</strong></a> and it said one method for changing tunable parameters in the Linux VM was the command:</p>
  
  <pre><code>sysctl -w vm.max_map_count=65535
  </code></pre>
  
  <p>I want to know what the number 65535 means and how much memory could vm use by the setting.</p>