title: Netty threads being blocked
body: <p>I have 3 ThreadPoolExecutors in my system.</p>
  
  <p>One for Netty's Master process, another for netty's worker process and last one for processing ad-hoc processing (sending request to mail server).</p>
  
  <pre><code>ExecutorService bossExecutors = Executors.newFixedThreadPool(1, 
                   new ServerThreadFactory("netty-boss")); 
  ExecutorService workerExecutors = Executors.newFixedThreadPool(10, 
                   new ServerThreadFactory("netty-worker"));
  ChannelFactory factory = new NioServerSocketChannelFactory(
                   bossExecutors, 
                   workerExecutors,
                   Runtime.getRuntime().availableProcessors());
  
  ExecutorService mailExecutor = Executors.newFixedThreadPool(40);
  </code></pre>
  
  <p>This works perfectly fine until <code>mailExecutor</code> starts making request to mail server. Until, that batch requests using <code>mailExecutor</code>, generally making 5000+ requests to mail server is completed, netty threads get blocked.</p>
  
  <p>I don't understand why netty threads seem to be getting blocked that time since, I have allocated definite thread pools. During that time, Netty can't even process single request.</p>
  
  <p>Any idea why it's happening or what I'm doing wrong?</p>