title: Will Spring Integrations Task Scheduler Block is all threads in Task Executor are busy
body: <p>If all the threads in the taskExecutor are busy (All 100 of them). Will the threads used by the poller block? Or will the poller thread leave the message on the queue and try again in another 300ms? </p>
  
  <pre><code>&lt;int:channel id="tasksIn"&gt;
      &lt;int:queue capacity="50"/&gt;    
  &lt;/int:channel&gt;
  
  &lt;int:bridge input-channel="tasksIn" output-channel="taskProcessing" &gt;
      &lt;int:poller fixed-rate="300" max-messages-per-poll="2" /&gt;
  &lt;/int:bridge&gt;
  
  &lt;int:channel id="taskProcessing"&gt;
      &lt;int:dispatcher task-executor="executor"/&gt;
  &lt;/int:channel&gt;
  
  &lt;service-activator input-channel="taskProcessing" output-channel="taskCompleteChannel" ref="taskProcessor" method="processTask"/&gt;
  
  &lt;task:executor id="executor" pool-size="100" /&gt;
  </code></pre>