Latency issue while accessing server in multiple threads

[koguty]

Hi folks,
I am new to netty and need some help regarding latency issue :
implemented a simple server and client app using netty - 
the client sends a request and the server sends back a fixed resonse and
closes the channel;
while using multiple threads (say 10 threads) it takes almost 30 ms or more
to get the resonse from server.
This is in local machine - no network delays.
using the included test class for testing.

I have set child.tcpNoDelay in server and tcpNoDelay in client as true.

Query : 
1. is it possible to take the timing down to <10 milli secs? 
2. is the implementation wrong or anything wrong with the test case?

Please let me know.

Thanks in advance.

Test class : 
public class Test {
    private static int numOfSearchThreads = 10;
    private static ExecutorService search =
Executors.newFixedThreadPool(numOfSearchThreads);
    
    public static void main(String[] args) throws Exception
    {
        TimerTask task = new TimerTask() {
            public void run() {
                System.out.println();
                System.out.println("Starting multi search ... ");
                for (int i = 0; i < numOfSearchThreads; i++){
                    Runnable task = new Runnable() {
                        @Override
                        public void run() {
                            try {
                                long t0 = System.currentTimeMillis();
                               
Client.getInstance().getSubscriberFromServer();
                                System.out.println("Time taken : " +
(System.currentTimeMillis() - t0));
                            } catch (UnknownHostException e) {
                                e.printStackTrace();
                            }
                        }
                    };
                    search.submit(task);
                }
            }
        };
        new Timer().schedule(task, 0, 10 * 1000);
    }
    
}


Server : 
public class Server {
    public static final int PORT = 7007;
    public static void start(){
        ServerBootstrap bootstrap = new ServerBootstrap(
                new NioServerSocketChannelFactory(
                        Executors.newCachedThreadPool(),
                        Executors.newCachedThreadPool()));
        bootstrap.setOption("child.tcpNoDelay", true);
        bootstrap.getPipeline().addLast("handler", new
SearchServerHandler());
        bootstrap.bind(new InetSocketAddress(PORT));
    }
    public static void main(String[] args) throws Exception {
        start();
    }
}

class SearchServerHandler extends SimpleChannelHandler {
    private static final Logger logger =
Logger.getLogger(SearchServerHandler.class.getName());
    private static final ChannelBuffer
fixedResponse=ChannelBuffers.copiedBuffer("1".getBytes());
    public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
        e.getChannel().write(fixedResponse);
        e.getChannel().close();
    }
    public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
{
        logger.log(Level.WARNING, "Unexpected exception from downstream.",
e.getCause());
        e.getChannel().close();
    }
}



Client : 
public class Client {
	private static final String host = "localhost";
	private static final ExecutorService executor =
Executors.newCachedThreadPool();
	private static final ChannelFactory channelFactory = new
NioClientSocketChannelFactory(executor, executor);
	private static final ClientBootstrap bootstrap = new
ClientBootstrap(channelFactory);
	private static final Client instance = new Client(); 
	private static SocketAddress address;

	private Client(){
        bootstrap.setOption("tcpNoDelay", true);
        bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
			public ChannelPipeline getPipeline() throws Exception {
				return Channels.pipeline(new ClientHandler());
			}
		});
       	address = new InetSocketAddress(host, Server.PORT);
	}
	public static Client getInstance(){
		return instance;
	}
	public String getSubscriberFromServer() throws UnknownHostException{
        ChannelFuture future = bootstrap.connect(address);
        future.getChannel().getCloseFuture().awaitUninterruptibly();
		return "";
    }
    private ChannelFuture connect() throws UnknownHostException{
        ChannelFuture future = bootstrap.connect(address);
        future.getChannel().getCloseFuture().awaitUninterruptibly();
        return future;
    }
    public void shutdown(){
        bootstrap.releaseExternalResources();
    }
}

class ClientHandler extends SimpleChannelUpstreamHandler{
	private static final Logger logger =
Logger.getLogger(SearchClientHandler.class.getName());
    public void channelConnected(ChannelHandlerContext ctx,
ChannelStateEvent e) {
        e.getChannel().write(ChannelBuffers.copiedBuffer("1".getBytes()));
    }
    public void messageReceived(ChannelHandlerContext ctx, MessageEvent e)
throws Exception {
    	byte[] bytes = ((ChannelBuffer)e.getMessage()).array();
    	String s = new String(bytes);
        logger.info("obtained : " + s);
        e.getChannel().close();
    }
    public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
{
        logger.log(Level.WARNING, "Unexpected exception from downstream.",
e.getCause());
        e.getChannel().close();
    }
}
http://netty-forums-and-mailing-lists.685743.n2.nabble.com/file/n5428086/Client.java
Client.java 
http://netty-forums-and-mailing-lists.685743.n2.nabble.com/file/n5428086/Server.java
Server.java 
http://netty-forums-and-mailing-lists.685743.n2.nabble.com/file/n5428086/Test.java
Test.java 
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