title: OpenMP not using all available cores on Raspberry Pi 2
body: <p>I'm using <a href="https://github.com/gnebehay/OpenTLD" rel="noreferrer">OpenTLD</a> (that uses OpenCV for image analysis) in a Raspberry Pi 2 project for object tracking. In order to combat lag issues (about 3 seconds of video lag) I enabled OpenMP support when I compiled. Now, I get only about 2 seconds of lag. Running <code>top</code> tells me that at most only ~170% CPU is being used by <code>opentld</code>, leading me to suspect that OpenMP is using only two of the Raspberry Pi 2's <em>four</em> cores.</p>
  
  <p>From what I understand of <a href="https://upload.wikimedia.org/wikipedia/commons/f/f1/Fork_join.svg" rel="noreferrer">this Wikipedia diagram</a>, OpenMP should be able to utilize all four cores. Is this a matter of OpenMP not recognizing all the cores, or is it something else?</p>