Flume-ng 数据发送速度限制

转自：http://blog.csdn.net/desilting/article/details/27081357

   按理说，应该在sink端限制数据的发送速度，但flume-ng提供了非常便利的interceptor模式，因此本文，就只是在source端简单的实现了对数据发送速度的限制。

 package com.xxx.flume.core.interceptor;

 import java.util.List;
 import org.slf4j.Logger;
 import org.apache.flume.Event;
 import org.slf4j.LoggerFactory;
 import org.apache.flume.Context;
 import org.apache.flume.interceptor.Interceptor;


 public class LimitInterceptor implements Interceptor {
     private static final Logger logger = LoggerFactory.getLogger(LimitInterceptor.class);

     private static long KB = 1024L;

     private long lastEventSentTick = System.nanoTime();

     private long pastSentLength = 0L;
     private long max;
     private long timeCostPerCheck = 1000000000L;

     private long headerSize = 0L;

     private boolean flag = true;

     private int num = 0;

     public LimitInterceptor(long limitRate, long headerSize) {
         this.max = (limitRate * KB);
         this.headerSize = headerSize;
     }

     public void initialize() {
     }

     public Event intercept(Event event) {
         this.num += 1;
         if (this.pastSentLength > this.max) {
             long nowTick = System.nanoTime();
             long multiple = this.pastSentLength / this.max;
             long missedTime = multiple * this.timeCostPerCheck - (nowTick - this.lastEventSentTick);
             if (missedTime > 0L) {
                 try {
                     System.out.printf("Limit source send rate, headerLength:%d,pastSentLength:%d,lastEventSentTick:%d,sleepTime:%d, num:%d\n",
                         headerSize, pastSentLength, lastEventSentTick, missedTime / 1000000, num);
                     Thread.sleep(missedTime / 1000000L, (int) (missedTime % 1000000L));
                 } catch (InterruptedException e) {
                     e.printStackTrace();
                 }
             }
             this.num = 0;
             this.pastSentLength = 0L;
             this.lastEventSentTick = (nowTick + (missedTime > 0L ? missedTime : 0L));
         }
         this.pastSentLength += this.headerSize + event.getBody().length;

         return event;
     }

     public List intercept(List events) {
         for (Event event : events) {
             intercept(event);
         }
         return events;
     }

     public void close() {
     }

     public static class Builder implements Interceptor.Builder {
         private long limitRate;
         private long headerSize;

         public Interceptor build() {
             return new LimitInterceptor(this.limitRate, this.headerSize);
         }

         public void configure(Context context) {
             this.limitRate = context.getLong(Constants.LIMIT_RATE, Long.valueOf(Constants.DEFAULT_RATE)).longValue();
             this.headerSize = context.getLong(Constants.HEADER_SIZE, Long.valueOf(Constants.DEFAULT_SIZE)).longValue();
         }

         public static class Constants {
             public static long DEFAULT_RATE = 500L;
             public static long DEFAULT_SIZE = 16L;
             public static String LIMIT_RATE = "limitRate";
             public static String HEADER_SIZE = "headerSize";
         }
     }
 }

打包后扔到flume-ng的lib目录下，然后在flume-conf配置文件，增加流速拦截器：

 agent.sources.seqGenSrc.interceptors = limitrate
 agent.sources.seqGenSrc.interceptors.limitrate.type = com.xxx.flume.core.interceptor.LimitInterceptor$Builder
 agent.sources.seqGenSrc.interceptors.limitrate.limitRate = 500
 agent.sources.seqGenSrc.interceptors.limitrate.headerSize = 8

这里限制发送速度500kb/s（可以为不同的source设置不同的发送速度），设置每个event头大小约为8字节。

发送端输出信息：

 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649436601991827,sleepTime:929, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649437601991827,sleepTime:929, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649438601991827,sleepTime:929, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649439601991827,sleepTime:927, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649440601991827,sleepTime:928, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649441601991827,sleepTime:928, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649442601991827,sleepTime:928, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649443601991827,sleepTime:925, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649444601991827,sleepTime:929, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512025,lastEventSentTick:79649445601991827,sleepTime:889, num:3421
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649446601991827,sleepTime:924, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649447601991827,sleepTime:927, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSentTick:79649448601991827,sleepTime:928, num:3437
 Limit source send rate, headerLength:8,pastSentLength:512113,lastEventSen