Netty多线程配置机制

本文主要是对前一节（Netty多线程机制）中的一些未提及的有用的类（可控制可配置类）做进一步解释说明，由于NIO包和OIO包中类比较多，此文仅介绍与多线程相关的且有对外开放接口的类进行分析。

NIO包结构如下图所示：

本文档主要讲解此包中的

DefaultNioDatagramChannelConfig类、

NioDatagramChannelConfig接口、

NioSocketChannelConfig接口

 

OIO包结构如下图所示：

此包中的类各种功能与NIO包中的类的功能类似，只是适用于old I/O，添加了多播模式的支持。

参考源码包

以下是对类的具体说明以及重要的常用的方法的分析

DefaultNioDatagramChannelConfig

此类是接口NioDatagramChannelConfig的实现类，具体的使用方法参见3.2.NioDatagramChannelConfig接口分析

NioDatagramChannelConfig

为新的I/O(new I/O) TCP/IP协议提供数据报管道配置，主要是配置DatagramChannel的参数的。以下是一些常用的参数：

 

 

 

 

 

Name

Associated setter method

"writeBufferHighWaterMark"

默认64 * 1024（用法未知）

"writeBufferLowWaterMark"

默认32 * 1024（用法未知）

"writeSpinCount"

默认16（重复写次数，用法未知）

"broadcast"

true / false多播模式(UDP适用)

"interface"

多播数据包的网络接口地址

"loopbackModeDisabled"

实际调用的是channel.setOption(StandardSocketOptions.IP_MULTICAST_LOOP, loopbackModeDisabled);仅针对JDK7+有效

"networkInterface"

实际调用的是channel.setOption(StandardSocketOptions.IP_MULTICAST_IF, networkInterface);仅针对JDK7+有效

"reuseAddress"

地址是否可复用（UDP socket address绑定时用到）

"receiveBufferSize"

数据包接收大小

"receiveBufferSizePredictor"

数据包接收大小：默认设置为FixedReceiveBufferSizePredictor(768)，超过后丢弃

"receiveBufferSizePredictorFactory"

似乎与上面的功能相同，设置方式：new FixedReceiveBufferSizePredictorFactory(1024)

"sendBufferSize"

发送数据包大小

"timeToLive"

JDK7+版本有效

"trafficClass"

0<=tc<=255

bufferFactory"

用于创建ChannelBuffer的工厂，默认HeapChannelBufferFactory

"connectTimeoutMillis"

连接超时时间（毫秒）

"pipelineFactory"

仅适用于child channel创建时有效

"keepAlive"

启用/禁用Nagle算法

"soLinger"

Socket关闭时的延迟时间（单位：秒）

"tcpNoDelay"

启用/禁用Nagle算法

 

 

 

NioSocketChannelConfig

具体配置查看3.2 NioDatagramChannelConfig

Demo实现

SocketSetver

publicstaticvoid tcpServerStartUp() {

        TCPSERVER_BOOTSTRAP.setPipelineFactory(new TCPServerPipelineFactory(EXECUTION_UP_HANDLER,EXECUTION_DOWN_HANDLER));

//        TCPSERVER_BOOTSTRAP.setOption("child.tcpNoDelay", true);

//        TCPSERVER_BOOTSTRAP.setOption("child.keepAlive", true);

//        TCPSERVER_BOOTSTRAP.setOption("reuseAddress", true);

//        LOGGER.info("SERVER_NAME:"+Constants.SERVER_NAME);

//        LOGGER.info("TCPSERVER_PORT:"+Constants.TCPSERVER_PORT);

//        TCPSERVER_BOOTSTRAP.bind(new InetSocketAddress(Constants.SERVER_NAME,Constants.TCPSERVER_PORT));

        TCPSERVER_BOOTSTRAP.setOptions(Constants.CHANNEL_CONFIGER_MAP);

        TCPSERVER_BOOTSTRAP.bind();

        LOGGER.info("TCP服务已启动....");

Constants

 

CHANNEL_CONFIGER_MAP.put("writeBufferHighWaterMark", 64*1024);

        CHANNEL_CONFIGER_MAP.put("writeBufferLowWaterMark", 32*1024);

        CHANNEL_CONFIGER_MAP.put("writeSpinCount", 16);

        CHANNEL_CONFIGER_MAP.put("broadcast",true);

        CHANNEL_CONFIGER_MAP.put("interface",new InetSocketAddress(Constants.SERVER_NAME,Constants.TCPSERVER_PORT));

        CHANNEL_CONFIGER_MAP.put("loopbackModeDisabled",true);

        CHANNEL_CONFIGER_MAP.put("networkInterface",new InetSocketAddress(Constants.SERVER_NAME,Constants.TCPSERVER_PORT));

        CHANNEL_CONFIGER_MAP.put("localAddress",new InetSocketAddress(Constants.SERVER_NAME,Constants.TCPSERVER_PORT));

        CHANNEL_CONFIGER_MAP.put("reuseAddress",true);

        CHANNEL_CONFIGER_MAP.put("receiveBufferSize", 10000);

        CHANNEL_CONFIGER_MAP.put("receiveBufferSizePredictor",new FixedReceiveBufferSizePredictor(100000));

        CHANNEL_CONFIGER_MAP.put("receiveBufferSizePredictorFactory",new FixedReceiveBufferSizePredictorFactory(100000));

        CHANNEL_CONFIGER_MAP.put("sendBufferSize", 10000);

        CHANNEL_CONFIGER_MAP.put("timeToLive", 30);

        CHANNEL_CONFIGER_MAP.put("trafficClass", 100);

        CHANNEL_CONFIGER_MAP.put("bufferFactory",new HeapChannelBufferFactory());

        CHANNEL_CONFIGER_MAP.put("connectTimeoutMillis", 60000);

        CHANNEL_CONFIGER_MAP.put("pipelineFactory",new TCPServerPipelineFactory(new ExecutionHandler(

    new OrderedMemoryAwareThreadPoolExecutor(16, 1048576, 1048576),false,true),new ExecutionHandler(

    new OrderedDownstreamThreadPoolExecutor(16),true,false)));