ServerBootstrap sbs = new ServerBootstrap(); // 配置nio服务参数 sbs.group(bossGroup, workerGroup) .channel(NioServerSocketChannel.class) // 说明一个新的Channel如何接收进来的连接 .option(ChannelOption.SO_BACKLOG, 128) // tcp最大缓存链接个数 .childOption(ChannelOption.SO_KEEPALIVE, true) //保持连接 .handler(new LoggingHandler(LogLevel.INFO)) // 打印日志级别 .childHandler(new ChannelInitializer<SocketChannel>() { @Override protected void initChannel(SocketChannel socketChannel) throws Exception { // 处理接收到的请求 ChannelPipeline pipeline = socketChannel.pipeline(); // 基于换行符号 // pipeline.addLast(new LineBasedFrameDecoder(1024)); // 这个会导致 channelRead0 没有执行,因为 数据一直在接收之中.. 等待一个换行 // 解码转String,注意调整自己的编码格式GBK、UTF-8 pipeline.addLast(new StringDecoder(Charset.forName("GBK"))); // 解码转String,注意调整自己的编码格式GBK、UTF-8 pipeline.addLast(new StringEncoder(Charset.forName("GBK"))); //流量整形 // pipeline.addLast(new ChannelTrafficShapingHandler(10, 10)); pipeline.addLast(new MyServerCommonHandler( ));
管道处理器:
import io.netty.channel.*; import java.util.Date; import java.util.Optional; import java.util.concurrent.atomic.AtomicLong; import java.util.function.Consumer; public class MyServerCommonHandler extends ChannelInboundHandlerAdapter { protected final int KB = 1024;// * 1024; protected String tempStr; protected AtomicLong consumeMsgLength; protected Runnable counterTask; protected boolean sentFlag; @Override public void channelWritabilityChanged(ChannelHandlerContext ctx) throws Exception { if(ctx.channel().isWritable() && !sentFlag) { System.out.println(" ###### 重新开始写数据 ######"); } else { System.out.println(" ===== 写暂停 ====="); } } @Override public void handlerAdded(ChannelHandlerContext ctx) throws Exception { System.out.println("MyServerCommonHandler.handlerAdded"); consumeMsgLength = new AtomicLong(); counterTask = () -> { while (true) { try { Thread.sleep(1000); } catch (InterruptedException e) { } long length = consumeMsgLength.getAndSet(0); System.out.println("*** " + ctx.channel().remoteAddress() + " rate(KB/S):" + (length) + " " + new Date()); } }; StringBuilder builder = new StringBuilder(); for (int i = 0; i < KB; i++) { builder.append("abcdefghijklmnopqrstuvwxyz"); } tempStr = builder.toString(); super.handlerAdded(ctx); } @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { new Thread(counterTask).start(); } protected abstract void sentData(ChannelHandlerContext ctx); @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { if (msg instanceof String) { int length = ((String) msg).length(); // // 为什么这里 是默认 15s 一次, 因为io.netty.handler.traffic.AbstractTrafficShapingHandler.DEFAULT_MAX_TIME = 15 000 long l = consumeMsgLength.addAndGet(length);// 为什么每次都是 10240 ? 因为客户端写过来的数据就是这么多 System.out.println("===== receive client " + " " + " size:" + l); } // System.out.println("===== receive client msg : " + msg + " \n " + l); super.channelRead(ctx, msg); } }
@Override protected void initChannel(SocketChannel socketChannel) throws Exception { // 处理来自服务端的响应信息 ChannelPipeline pipeline = socketChannel.pipeline(); ChannelTrafficShapingHandler channelTrafficShapingHandler = new MyChannelTrafficShapingHandler((long) (0.001 * KB), 1 * KB); // 解码转String,注意调整自己的编码格式GBK、UTF-8 pipeline.addLast(new StringDecoder(Charset.forName("GBK"))); // 解码转String,注意调整自己的编码格式GBK、UTF-8 pipeline.addLast(new StringEncoder(Charset.forName("GBK"))); pipeline .addLast("channelTrafficShapingHandler",channelTrafficShapingHandler) .addLast(new ClientOutHandler())
上面设置是:writeLimit = 0.001 * KB,也就是 每秒最多写 0.001 * KB,
管道处理器:
import com.zx.sms.testNetty.Student; import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.channel.ChannelOutboundHandlerAdapter; import io.netty.channel.ChannelPromise; import io.netty.util.ReferenceCountUtil; import java.net.SocketAddress; import java.nio.charset.Charset; import java.util.Date; /** * 读取服务器返回的响应信息 * @author luo * */ public class ClientOutHandler extends ChannelOutboundHandlerAdapter { @Override public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception { System.out.println("write = " + new Date() + " ctx.channel().isWritable() " + ctx.channel().isWritable()); super.write(ctx, msg, promise); } @Override public void disconnect(ChannelHandlerContext ctx, ChannelPromise promise) throws Exception { System.out.println("ClientOutHandler.disconnect" + new Date()); super.disconnect(ctx, promise); } @Override public void read(ChannelHandlerContext ctx) throws Exception { System.out.println("ClientOutHandler.read" + new Date()); super.read(ctx); } @Override public void close(ChannelHandlerContext ctx, ChannelPromise promise) throws Exception { System.out.println("ClientOutHandler.close" + new Date()); super.close(ctx, promise); } @Override public void connect(ChannelHandlerContext ctx, SocketAddress remoteAddress, SocketAddress localAddress, ChannelPromise promise) throws Exception { System.out.println("ctx = [" + ctx + "], remoteAddress = [" + remoteAddress + "], localAddress = [" + localAddress + "], promise = [" + promise + "]" + new Date()); super.connect(ctx, remoteAddress, localAddress, promise); new Thread() { @Override public void run() { StringBuilder builder = new StringBuilder(); for (int i = 0; i < 1024*1; i++) { builder.append("abcdefghij"); } int cnt = 0; String o = builder.toString(); while (cnt < 1000) { try { Thread.sleep(100); } catch (InterruptedException e) { e.printStackTrace(); } boolean writable = ctx.channel().isWritable(); /* 因为io.netty.handler.traffic.AbstractTrafficShapingHandler.DEFAULT_MAX_TIME 所以 无论, 都会写一次。 */ if (writable) { ctx.channel().writeAndFlush(o); } else{ // System.out.println("ClientOutHandler.run ctx.channel().isWritable() no"); } cnt++; } } }.start(); } @Override public void flush(ChannelHandlerContext ctx) throws Exception { super.flush(ctx); } @Override public void deregister(ChannelHandlerContext ctx, ChannelPromise promise) throws Exception { System.out.println("ctx = [" + ctx + "], promise = [" + promise + "] " + new Date() + " ctx.channel().isWritable() " + ctx.channel().isWritable()); super.deregister(ctx, promise); } @Override public void handlerAdded(ChannelHandlerContext ctx) throws Exception { System.out.println("ctx = [" + ctx + "] " + new Date()); super.handlerAdded(ctx); } }
*** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:21 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:22 CST 2021 ===== receive client size:10240 MyServerCommonHandler.channelReadComplete Sat May 29 20:38:22 CST 2021 *** /127.0.0.1:33533 rate(KB/S):10240 Sat May 29 20:38:23 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:24 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:25 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:26 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:27 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:28 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:29 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:30 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:31 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:32 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:33 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:34 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:35 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:36 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:37 CST 2021 ===== receive client size:10240 MyServerCommonHandler.channelReadComplete Sat May 29 20:38:37 CST 2021 *** /127.0.0.1:33533 rate(KB/S):10240 Sat May 29 20:38:38 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:39 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:40 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:41 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:42 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:43 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:44 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:45 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:46 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:47 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:48 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:49 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:50 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:51 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:52 CST 2021 ===== receive client size:10240 MyServerCommonHandler.channelReadComplete Sat May 29 20:38:52 CST 2021 *** /127.0.0.1:33533 rate(KB/S):10240 Sat May 29 20:38:53 CST 2021 *** /127.0.0.1:33533 rate(KB/S):0 Sat May 29 20:38:54 CST 2021
write = Sat May 29 20:37:37 CST 2021 ctx.channel().isWritable() true write = Sat May 29 20:37:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 20:38:07 CST 2021 ctx.channel().isWritable() true write = Sat May 29 20:38:22 CST 2021 ctx.channel().isWritable() true write = Sat May 29 20:38:37 CST 2021 ctx.channel().isWritable() true write = Sat May 29 20:38:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 20:39:07 CST 2021 ctx.channel().isWritable() true
write = Sat May 29 23:14:34 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:34 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:34 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:39 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:39 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:39 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:39 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:39 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:44 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:44 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:44 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:44 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:44 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:49 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:49 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:49 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:49 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:49 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:54 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:54 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:54 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:54 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:54 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:59 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:59 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:59 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:59 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:14:59 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:04 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:04 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:04 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:04 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:04 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:09 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:09 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:09 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:09 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:09 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:14 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:14 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:14 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:14 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:14 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:19 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:19 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:19 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:19 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:19 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:24 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:15:24 CST 2021 ctx.channel().isWritable() true
===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:25 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:25 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:26 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:26 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:27 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:27 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:28 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:28 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:29 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:29 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:30 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:30 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:31 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:31 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:32 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:32 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:33 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:33 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:34 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:34 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:35 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:35 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:36 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:36 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:37 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:37 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:38 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:38 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:39 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:39 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:45:40 CST 2021 *** /127.0.0.1:40279 rate(KB/S):1024 Sat May 29 23:45:40 CST 2021
可见并不符合预期!
void checkWriteSuspend(ChannelHandlerContext ctx, long delay, long queueSize) { if (queueSize > maxWriteSize || delay > maxWriteDelay) { setUserDefinedWritability(ctx, false); } }
===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:23 CST 2021 ===== receive client size:2048 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:24 CST 2021 *** /127.0.0.1:41167 rate(KB/S):2048 Sat May 29 23:53:24 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:24 CST 2021 ===== receive client size:2048 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:25 CST 2021 *** /127.0.0.1:41167 rate(KB/S):2048 Sat May 29 23:53:25 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:25 CST 2021 ===== receive client size:2048 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:26 CST 2021 *** /127.0.0.1:41167 rate(KB/S):2048 Sat May 29 23:53:26 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:26 CST 2021 ===== receive client size:2048 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:27 CST 2021 *** /127.0.0.1:41167 rate(KB/S):2048 Sat May 29 23:53:27 CST 2021 ===== receive client size:1024 MyServerCommonHandler.channelReadComplete Sat May 29 23:53:27 CST 2021 ===== receive client size:2048
发现其中 ===== receive client 打印了 2次, 分别是1024 2048 ,rate(KB/S)才打印一次 固定是 2048,这个是因为 服务端收到2次(每次手动1KB数据)后才会清零计数器。 rate 是正确的,其他打印也是正确的!
write = Sat May 29 23:51:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:52 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:53 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:53 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:53 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:53 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:57 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:57 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:57 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:57 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:57 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:57 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:58 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:58 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:58 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:51:58 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:02 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:02 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:02 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:02 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:02 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:02 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:03 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:03 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:03 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:03 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:07 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:07 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:07 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:07 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:07 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:07 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:08 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:08 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:08 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:08 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:15 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:16 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:21 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:21 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:21 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:21 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:21 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:21 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:22 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:22 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:22 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:22 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:26 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:26 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:26 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:26 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:26 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:26 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:27 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:27 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:27 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:27 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:34 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:35 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:40 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:40 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:40 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:40 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:40 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:40 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:41 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:41 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:41 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:41 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:45 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:45 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:45 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:45 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:45 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:45 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:46 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:46 CST 2021 ctx.channel().isWritable() true write = Sat May 29 23:52:46 CST 2021 ctx.channel().isWritable() true
观察发现 基本上 平均是 每5秒写10次,一次一行一kB! 就是翻倍了, 即 avg rate = 2k/s!
void submitWrite(final ChannelHandlerContext ctx, final Object msg, final long size, final long delay, final long now, final ChannelPromise promise) { final ToSend newToSend; // write order control synchronized (this) { if (delay == 0 && messagesQueue.isEmpty()) { trafficCounter.bytesRealWriteFlowControl(size); ctx.write(msg, promise); return; } newToSend = new ToSend(delay + now, msg, promise); messagesQueue.addLast(newToSend); queueSize += size; checkWriteSuspend(ctx, delay, queueSize); // @1 } final long futureNow = newToSend.relativeTimeAction; ctx.executor().schedule(new Runnable() { @Override public void run() { sendAllValid(ctx, futureNow); } }, delay, TimeUnit.MILLISECONDS); }
checkWriteSuspend 方法其实没有返回值,就是说它 仅仅是一个优化,即使没有立即的设置管道的可写性,也仅仅是影响可写性,如果此时有数据继续可过来, 此时会写到本地内存缓存中去! 而且,只要delay != 0 ,那么就不会立即return,那么就会提交一个延迟任务(不管是否可写),任务的执行是时间是未来时间: futureNow 。
如果把写速度不变,限速提高到1MB,那么就是相当于没有了限速。
按理说,当前提交了1个延迟任务,sendAllValid 方法就会执行对应的1次的写! 但是从sendAllValid源码来看,它有一个循环, 当内存中的缓冲队列messagesQueue 写完为空之后,又会release WriteSuspended ( 后面的需要等待前面的写完) 如果第1秒的时候 一个请求req1 过来,写很多数据,需要延迟10s 即第11s执行; 如果第2秒的时候 又一个请求req2 过来,写很多数据,需要延迟3s 即第5s执行,那么 req2 是会比req1 先执行吗? 还是说必须排队到 req1之后? 观察 io.netty.handler.traffic.TrafficCounter#writeTimeToWait(long, long, long, long) 可知,返回的wait 即 delay 是在本窗口中递增的数值,是第二个情况, 所以 req2 实际是 10 +3 第13s执行, 所以 第10秒 写完 req1之后, messagesQueue 还有一个数据,不为空 ,所以 保证了 release WriteSuspended 不是很频繁, 不会反复的被无谓的执行。
所以一般就是先wait的先write,但是 并发的情况下就不一定了! 所以上面 还有synchronized 加锁。
综上,基本上来说 客户端的数据 也都是按照设定的时间写出去的,大部分是平滑的。 但是如果发送的速度过快或数据量过大超出了限速,那么仍然有可能在超时的时刻有突刺。
futureNow