title: Jenkins AWS Spot fleet plugin doesn't automatically scale spot instances
body: <p>Planned to use EC2 Spot instance/fleet as our jenkins slave solution based on this article <a href="https://jenkins.io/blog/2016/06/10/save-costs-with-ec2-spot-fleet/" rel="noreferrer">https://jenkins.io/blog/2016/06/10/save-costs-with-ec2-spot-fleet/</a>.</p>
  
  <p><strong>EXCEPTED</strong><br>
  if the spot instances nodes remain free for the specified idle time (I have configured for 5 minutes), then Jenkins releases the nodes, and my Spot fleet nodes will be automatically scaled down. </p>
  
  <p><strong>ACTUAL</strong><br>
   my spot instances is still running for days.Also, noticed when I have more pending jobs, Jenkins does not automatically scale my Spot fleet to add more nodes.</p>
  
  <p>Automatic scale up/down supposed to be triggered automatically by aws service? or is this supposed to be triggered by the jenkins plugin? </p>
  
  <p><strong>CONFIGURATION</strong><br>
  Jenkins version : 2.121.2-1.1<br>
  EC2 Fleet Jenkins Plugin version : 1.1.7<br>
  Spot instance configuration :<br></p>
  
  <ul>
  <li>Request type : request &amp; maintain<br> </li>
  <li>Target Capacity : 1<br></li>
  </ul>
  
  <p>Spot fleet plugin configuration :<br></p>
  
  <ul>
  <li>Max Idle Minutes Before Scaledown : 5<br> </li>
  <li>Minimum Cluster Size : 0<br>  </li>
  <li>Maximum Cluster Size : 3<br></li>
  </ul>
  
  <p>Any help or lead would be really appreciated.</p>