Getting DirectBuffer OOM when sending fragmented binary message to websocket endpoint

1) Start EAP 7 (use default JAVA_OPTS defined in standalone.conf => JAVA_OPTS="-server -XX:+UseCompressedOops -server -XX:+UseCompressedOops -Xms64m -Xmx512m -Djava.net.preferIPv4Stack=true -Djboss.modules.system.pkgs=org.jboss.byteman -Djava.awt.headless=true" 2) Deploy simple web application with websocket endpoint which just echo's messages, see [1] 3) Install autobahn testsuite http://autobahn.ws/testsuite/installation.html#installation 4) Run test case "9.4.1" (good case to easily reproduce the issue) [1] @ServerEndpoint( "/echoBasicEndpoint" ) public class EchoBasicEndpoint { Writer writer; OutputStream stream; @OnMessage public void handleMessage( final String message, Session session, boolean last) throws IOException { if (writer == null ) { writer = session.getBasicRemote().getSendWriter(); } writer.write(message); if (last) { writer.close(); writer = null ; } } @OnMessage public void handleMessage( final byte [] message, Session session, boolean last) throws IOException { if (stream == null ) { stream = session.getBasicRemote().getSendStream(); } stream.write(message); stream.flush(); if (last) { stream.close(); stream = null ; } } @OnError public void onError(Throwable t) { System .err.println( "onError event occured: " + t.getMessage()); t.printStackTrace(); }