We need advice for a server software implementation with Java NIO

Question

I'm trying to calculate the load on a server I have to build.

I need to create a server witch have one million users registered in an SQL database. During a week each user will approximately connect 3-4 times. Each time a user will up and download 1-30 MB data, and it will take maybe 1-2 minutes.

When an upload is complete it will be deleted within minutes. (Update text removed error in calculations)

I know how to make and query an SQL database but what to consider in this situation?

Answer 1

What you want exactly is Netty. It's an API written in NIO and provides another event driven model instead of the classic thread model. It doesn't use a thread per request, but it put the requests in a queue. With this tool you can make up to 250,000 requests per second.

Answer 2

I am using Netty for a similar scenario. It is just working!

Here is a starting point for using netty:

public class TCPListener {
    private static ServerBootstrap bootstrap;

    public static void run(){
        bootstrap = new ServerBootstrap(
                new NioServerSocketChannelFactory(
                        Executors.newCachedThreadPool(),
                        Executors.newCachedThreadPool()));

        bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
            public ChannelPipeline getPipeline() throws Exception {
                TCPListnerHandler handler = new MyHandler();
                ChannelPipeline pipeline = Channels.pipeline();
                pipeline.addLast("handler", handler);

                return pipeline;
            }
        });

        bootstrap.bind(new InetSocketAddress(9999));  //port number is 9999
    }

    public static void main(String[] args) throws Exception {
        run();
    }
}

and MyHandler class:

public class MyHandler extends SimpleChannelUpstreamHandler {
    @Override
    public void messageReceived(
        ChannelHandlerContext ctx, MessageEvent e) {


        try {
            String remoteAddress = e.getRemoteAddress().toString();
            ChannelBuffer buffer= (ChannelBuffer) e.getMessage();
            //Now the buffer contains byte stream from client.

        } catch (UnsupportedEncodingException ex) {
            ex.printStackTrace();
        }

        byte[] output; //suppose output is a filled byte array
        ChannelBuffer writebuffer = ChannelBuffers.buffer(output.length);
        for (int i = 0; i < output.length; i++) {
            writebuffer.writeByte(output[i]);
        }


        e.getChannel().write(writebuffer);
    }

    @Override
    public void exceptionCaught(
            ChannelHandlerContext ctx, ExceptionEvent e) {
        // Close the connection when an exception is raised.
        e.getChannel().close();
    }
}