title: Spring Stream Listener Polling Stuck
body: <p>We have Spring Stream Listener that operates in BATCH mode.The processing time for each batch is about 3 ms.Following is our configuration: </p>
  
  <pre><code>allow.auto.create.topics = true
  auto.commit.interval.ms = 100
  auto.offset.reset = earliest
  connections.max.idle.ms = 540000
  default.api.timeout.ms = 60000
  enable.auto.commit = false
  fetch.max.bytes = 5242880
  fetch.max.wait.ms = 300000
  fetch.min.bytes = 2097152
  heartbeat.interval.ms = 3000
  isolation.level = read_uncommitted
  max.partition.fetch.bytes = 1048576
  max.poll.interval.ms = 300000
  max.poll.records = 500
  metadata.max.age.ms = 300000
  receive.buffer.bytes = 65536
  reconnect.backoff.max.ms = 1000
  reconnect.backoff.ms = 50
  request.timeout.ms = 330000
  retry.backoff.ms = 100
  </code></pre>
  
  <p>We see the following behaviour</p>
  
  <pre><code>May 23, 2020 @ 23:43:48.572 Consumed 463 messages  
  May 23, 2020 @ 23:43:47.791 Consumed 500 messages  
  --- 5 mins Gap ---                                 
  May 23, 2020 @ 23:38:47.764 Consumed 17 messages   
  May 23, 2020 @ 23:38:47.386 Consumed 500 messages  
  May 23, 2020 @ 23:38:46.989 Consumed 500 messages  
  May 23, 2020 @ 23:38:46.540 Consumed 500 messages  
  --- 5 mins Gap ---                                 
  May 23, 2020 @ 23:33:46.514 Consumed 106 messages  
  May 23, 2020 @ 23:33:46.155 Consumed 500 messages  
  May 23, 2020 @ 23:33:45.785 Consumed 500 messages  
  May 23, 2020 @ 23:33:45.358 Consumed 500 messages  
  </code></pre>
  
  <p>We see a 5 mins gap before we get next set of messages as seen above; this pattern continues.</p>
  
  <p>We have huge amount of messages in the Kafka partition waiting to be processed. So there is no dearth of ready messages. </p>
  
  <p>Not sure why we get 5 mins silence repeatedly - we have max poll wait/ poll interval all set to 5 mins. This should be okay since the max poll records of 500 can be satisfied immediately on poll.</p>
  
  <p>Fetch min bytes is 2 MB and max bytes is 5 MB; which again can be satisfied by the number of messages we have.</p>
  
  <p>Please let me know what am I missing. </p>