Java I / O vs NIO: Comparaison rapide des Benchmarks

J'ai récemment lu que dans les ordinateurs plus récents, les E/S de Java fonctionnent mieux que NIO en raison de la nouvelle disponibilité des machines multi-cœurs.

J'ai effectué un test rapide comparant le temps de transfert des E/S et des NIO sur le réseau local en utilisant l'adresse de bouclage localhost.

Remarque: Cela utilise JDK 7

Les résultats (3 essais):

Transferts d'e/S en moyenne 21789.3 ms

Transferts NIO en moyenne 22771.0 ms

Il vaut également la peine notant que l'utilisation du PROCESSEUR semblait être environ 10% plus élevée sur chaque transfert NIO par rapport aux E/S.

Ma question pour vous est de savoir si mon code de comparaison est juste? Ai-je écrit du code d'E/S et NIO bon/égal? Sinon, comment puis-je améliorer et relancer ce test?

    public static void main(String[] args) {
    System.out.println("Initiating test sequence...");
    new Thread(new Client()).start();
    try {
        System.out.println("Server I/O initiating...");
        ServerSocket server = new ServerSocket(5555);
        Socket sock = server.accept();
        System.out.println("Server connected to client successfully");
        InputStream is = sock.getInputStream();
        File output = new File("C:/test_root/video.avi");
        FileOutputStream fos = new FileOutputStream(output);
        byte[] data = new byte[1024];
        int len=0;
        System.out.println("Server initiating transfer - Timer starting");
        long start = System.currentTimeMillis();
        while((len=is.read(data))>0) {
            fos.write(data, 0, len);
            fos.flush();
        }
        fos.close();
        is.close();
        sock.close();
        server.close();
        long end = System.currentTimeMillis();
        System.out.println("Network I/O transfer time = "+(end-start)+"ms");

        System.out.println("Server NIO initiating...");
        ServerSocketChannel serverChan = ServerSocketChannel.open();
        serverChan.bind(new InetSocketAddress(5555));
        SocketChannel chan = serverChan.accept();
        chan.configureBlocking(false);
        System.out.println("Server channel connected");
        FileChannel fc = (FileChannel) Files.newByteChannel(Paths.get("C:/test_root/video.avi"), StandardOpenOption.CREATE, StandardOpenOption.WRITE);
        ByteBuffer buff = ByteBuffer.allocate(1024);
        System.out.println("Server initiating transfer - Timer starting");
        start = System.currentTimeMillis();
        while(chan.read(buff)>=0 || buff.position() > 0) {
            buff.flip();
            fc.write(buff);
            buff.compact();
        }
        chan.close();
        fc.close();
        serverChan.close();
        end = System.currentTimeMillis();
        System.out.println("Network NIO transfer time = "+(end-start)+"ms");
    } catch (IOException e) {
        e.printStackTrace();
    }
    System.out.println("Test completed!");
}

static class Client implements Runnable {

    public void run() {
        try {
            System.out.println("Client I/O initiating...");
            Socket sock = new Socket("localhost", 5555);
            System.out.println("Client connected to server successfully!");
            OutputStream os = sock.getOutputStream();
            File input = new File(System.getProperty("user.home")+"/Documents/clip0025.avi");
            FileInputStream fis = new FileInputStream(input);
            byte[] data = new byte[1024];
            int len=0;
            int tot=0;
            int perc=0;
            while((len=fis.read(data))>0) {
                os.write(data, 0, len);
                os.flush();
                tot+=len;
                int prev = perc;
                perc = getPercentage(tot, input.length());
                if(perc !=prev && (perc == 10 || perc == 25 || perc == 50 || perc == 75 || perc == 98))
                    System.out.println("Client reporting: "+perc+"% read");
            }
            os.close();
            fis.close();
            sock.close();

            try {
                Thread.sleep(2000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("Client NIO initiating...");
            SocketChannel sc = SocketChannel.open();
            boolean connected = sc.connect(new InetSocketAddress("localhost",5555));
            if(!connected)
                connected = sc.finishConnect();
            if(!connected)
                throw(new IOException("Client failed to connect"));
            System.out.println("Client channel connected");
            sc.configureBlocking(false);
            FileChannel fc = (FileChannel) Files.newByteChannel(input.toPath(), StandardOpenOption.READ);
            ByteBuffer buff = ByteBuffer.allocate(1024);
            len=0;
            tot=0;
            while((len=fc.read(buff))>=0||buff.position()>0) {
                buff.flip();
                sc.write(buff);
                buff.compact();
                tot+=len;
                int prev = perc;
                perc = getPercentage(tot, input.length());
                if(perc !=prev && (perc == 10 || perc == 25 || perc == 50 || perc == 75 || perc == 98))
                    System.out.println("Client reporting: "+perc+"% read");
            }
            sc.close();
            fc.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Informations supplémentaires:

1ère génération i7 quad-core processeur 2.67 GHz

6 Go DE RAM

Architecture 64 bits