title: Understand Prometheus Metrics Pulling
body: <p>I'm still not quite understand the Prometheus Metrics Pulling after reading and trying it. </p>
  
  <p>Say I have a telegraf agent that sends metrics over to Prometheus every 5 seconds. </p>
  
  <ul>
  <li>Prometheus should be configured to pull every 5 seconds right? But what if there are several seconds gap between the push and pull (ok that push and pull not happen at the same time)? What if Prometheus is configured to pull every 7 seconds?</li>
  <li>What if Prometheus is configured to pull every 15 seconds? Only one out 3 push get pulled? Will telegraf agent be fussy about that?</li>
  <li>What if Prometheus is configured to pull every 30 or even 60 seconds? Is the pulled value of that point of time, or average over 30 / 60 seconds?</li>
  </ul>
  
  <p>Lastly, can Prometheus pulling interval be changed during run-time? I want to reduce the pulling interval to every 30 or even 60 seconds at night. </p>