如何简单地测算系统吞吐量

在流计算、数据传输之类的系统中，有时候需要统计、压测下一下系统的吞吐能力，这里写了一段简单实现记录一下，方便以后使用，构造参数有两个，一个是name，用于区分，一个是采样周期。

发送或者接收代码中调用update方法即可

[code]public class ThroughputProbe extends TimerTask {
     private static Logger log = Logger.getLogger(ThroughputProbe.class);
     private long count = 0;
     private int sampleCount = 0;
     private long samplingRateInSeconds;
     private String name;
     private double maxThroughput = 0.0;
     private double minThroughput = Double.MAX_VALUE;
     private double accumulatedThroughput = 0.0;
     DecimalFormat formatter = new DecimalFormat("#.000");
     Timer timer;
     private long totalEventCount = 0;

public ThroughputProbe(String name, int samplingRateInSeconds){
    this.name = name;
    this.samplingRateInSeconds = samplingRateInSeconds;
}

public void startSampling(){
    count = 0l;
    timer = new Timer();
    timer.schedule(this, samplingRateInSeconds * 1000, samplingRateInSeconds * 1000);
}

public void update(){
    count++;
    totalEventCount++;
}

@Override
public void run() {
    if (log.isDebugEnabled()){
        if (totalEventCount > 0){
            double throughput = count / samplingRateInSeconds;

            if (maxThroughput < throughput){
                maxThroughput = throughput;
            }
            if (minThroughput > throughput && throughput != 0.0){
                minThroughput = throughput;
            }

            accumulatedThroughput += throughput;
            sampleCount++;

            log.debug("[ThroughputProbe:" + name + "] " + count + " events in " + samplingRateInSeconds
                    + " seconds. Throughput=" + formatter.format(throughput)
                    + " events/s.(Avg=" + formatter.format(accumulatedThroughput / sampleCount)
                    + " ,Max=" + formatter.format(maxThroughput)
                    + " ,Min=" + ((minThroughput == Double.MAX_VALUE) ? "0.0" : formatter.format(minThroughput))
                    + " ) TotalEvents=" + totalEventCount);

            count = 0l;
        }
    }
}
}