Examples of ReceiveBufferSizePredictor

com.facebook.presto.jdbc.internal.netty.channel.ReceiveBufferSizePredictor

Predicts the number of readable bytes in the receive buffer of a {@link Channel}.

It calculates the close-to-optimal capacity of the {@link ChannelBuffer}for the next read operation depending on the actual number of read bytes in the previous read operation. More accurate the prediction is, more effective the memory utilization will be.

com.firefly.net.ReceiveBufferSizePredictor

io.netty.channel.ReceiveBufferSizePredictor

Predicts the number of readable bytes in the receive buffer of a {@link Channel}.

org.jboss.netty.channel.ReceiveBufferSizePredictor

Predicts the number of readable bytes in the receive buffer of a {@link Channel}.

Once a read operation is performed and the actual number of read bytes is known, an I/O thread will call {@link #previousReceiveBufferSize(int)} toupdate the predictor so it can predict more accurately next time. @author The Netty Project (netty-dev@lists.jboss.org) @author Trustin Lee (tlee@redhat.com) @version $Rev: 1406 $, $Date: 2009-06-17 18:33:20 +0900 (Wed, 17 Jun 2009) $

     *
     * @param key The selection key which contains the Selector registration information.
     */
    private static boolean read(final SelectionKey key) {
        final NioDatagramChannel channel = (NioDatagramChannel) key.attachment();
        ReceiveBufferSizePredictor predictor =
            channel.getConfig().getReceiveBufferSizePredictor();
        final ChannelBufferFactory bufferFactory = channel.getConfig().getBufferFactory();
        final DatagramChannel nioChannel = (DatagramChannel) key.channel();


        // Allocating a non-direct buffer with a max udp packge size.
        // Would using a direct buffer be more efficient or would this negatively
        // effect performance, as direct buffer allocation has a higher upfront cost
        // where as a ByteBuffer is heap allocated.
        final ByteBuffer byteBuffer = ByteBuffer.allocate(
                predictor.nextReceiveBufferSize()).order(bufferFactory.getDefaultOrder());


        boolean failure = true;
        SocketAddress remoteAddress = null;
        try {
            // Receive from the channel in a non blocking mode. We have already been notified that
            // the channel is ready to receive.
            remoteAddress = nioChannel.receive(byteBuffer);
            failure = false;
        } catch (AsynchronousCloseException e) {
            // Can happen, and does not need a user attention.
        } catch (Throwable t) {
            fireExceptionCaught(channel, t);
        }


        if (remoteAddress != null) {
            // Flip the buffer so that we can wrap it.
            byteBuffer.flip();


            int readBytes = byteBuffer.remaining();
            if (readBytes > 0) {
                // Update the predictor.
                predictor.previousReceiveBufferSize(readBytes);


                // Create a Netty ChannelByffer by wrapping the ByteBuffer.
                final ChannelBuffer channelBuffer = ChannelBuffers
                        .wrappedBuffer(byteBuffer);

All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.

Examples of ReceiveBufferSizePredictor

Examples of org.jboss.netty.channel.ReceiveBufferSizePredictor