title: Composer update `The following exception is caused by a lack of memory and not having swap configured` error in vagrant
body: <p>I got php5.5 with composer installed in a vagrant VirtualBox environment. </p>
  
  <p>When I try any composer's commands the following error appears randomly:</p>
  
  <p><code>The following exception is caused by a lack of memory and not having swap configured</code></p>
  
  <p>How can I get around this ?</p>