写一个基于TCP协议的netty服务器，要求workderLoopGroup只能由6个线程

非常感谢您的提问。以下是一个基于TCP协议的Netty服务器的示例代码，其中workerLoopGroup只有6个线程：

EventLoopGroup bossGroup = new NioEventLoopGroup(1);
EventLoopGroup workerGroup = new NioEventLoopGroup(6);

try {
    ServerBootstrap b = new ServerBootstrap();
    b.group(bossGroup, workerGroup)
     .channel(NioServerSocketChannel.class)
     .childHandler(new ChannelInitializer<SocketChannel>() {
         @Override
         public void initChannel(SocketChannel ch) throws Exception {
             ChannelPipeline p = ch.pipeline();
             p.addLast(new SomeHandler());
         }
     })
     .option(ChannelOption.SO_BACKLOG, 128)
     .childOption(ChannelOption.SO_KEEPALIVE, true);

    // Bind and start to accept incoming connections.
    ChannelFuture f = b.bind(port).sync();

    // Wait until the server socket is closed.
    f.channel().closeFuture().sync();
} finally {
    workerGroup.shutdownGracefully();
    bossGroup.shutdownGracefully();
}

希望这个示例代码能够帮助您。如果您有任何其他问题，请随时问我。