private CommunicationMode getCommunicationModeForNonSelector(Socket socket) throws IOException {
    socket.setSoTimeout(0);
    socketCreator.forCluster().handshakeIfSocketIsSSL(socket, acceptTimeout);
    byte communicationModeByte = (byte) socket.getInputStream().read();
    if (communicationModeByte == -1) {
      throw new EOFException();
    }
    return CommunicationMode.fromModeNumber(communicationModeByte);
  }
Hand off a new client connection to the thread pool that processes handshakes. If all the
threads in this pool are busy then the hand off will block until a thread is available. This
blocking is good because it will throttle the rate at which we create new connections.
geode-core/src/main/java/org/apache/geode/internal/cache/tier/sockets/AcceptorImpl.java