title: Memory leak in netty API
body: <p>I am new to netty API
  and I am using netty3.5.2 to develop client and server communication server,
  but the app always run full GC,
  I use jmap to dump the memory and
  use jhat to show which object occupied the memory.<br>
  And there are 6413363 instances of  <code>DefaultChannelFuture</code>.
  can someone tell which thread create the <code>DefaultChannelFuture</code> instances
  and how and  when they will be released?</p>
  
  <p>Top 4 instances suspected<br>
  6413363 instances of class <code>org.jboss.netty.channel.DefaultChannelFuture</code><br>
  631971  instances of class <code>org.jboss.netty.util.internal.LinkedTransferQueue$Node</code><br>
  630934  instances of class <code>org.jboss.netty.buffer.BigEndianHeapChannelBuffer</code><br>
  630767  instances of class <code>org.jboss.netty.channel.DownStreamMessageEvent</code></p>