title: flink - measuring backpressure
body: <p>Im doing some testing with <strong>Flink</strong> as comparison against some other streaming platforms. The datasource for the tests is a kafka topic with a varying amount of traffic and Im trying to figure out whether flink is keeping up. </p>
  
  <p>Is there a way to know how much 'backpressure' flink is putting on the kafka consumer? IE Is it keeping pace?</p>