com.yahoo.ycsb.measurements.SeriesUnit.java Source code

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Here is the source code for com.yahoo.ycsb.measurements.SeriesUnit.java

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/**                                                                                                                                                                                
 * Copyright (c) 2010 Yahoo! Inc. All rights reserved.                                                                                                                             
 *                                                                                                                                                                                 
 * Licensed under the Apache License, Version 2.0 (the "License"); you                                                                                                             
 * may not use this file except in compliance with the License. You                                                                                                                
 * may obtain a copy of the License at                                                                                                                                             
 *                                                                                                                                                                                 
 * http://www.apache.org/licenses/LICENSE-2.0                                                                                                                                      
 *                                                                                                                                                                                 
 * Unless required by applicable law or agreed to in writing, software                                                                                                             
 * distributed under the License is distributed on an "AS IS" BASIS,                                                                                                               
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or                                                                                                                 
 * implied. See the License for the specific language governing                                                                                                                    
 * permissions and limitations under the License. See accompanying                                                                                                                 
 * LICENSE file.                                                                                                                                                                   
 */

package com.yahoo.ycsb.measurements;

import java.io.IOException;
import java.text.DecimalFormat;
import java.util.HashMap;
import java.util.Properties;
import java.util.Vector;

import com.yahoo.ycsb.measurements.exporter.MeasurementsExporter;
import org.apache.commons.math.stat.descriptive.SummaryStatistics;

class SeriesUnit {
    /**
     * @param time
     * @param average
     */
    public SeriesUnit(long time, double average) {
        this.time = time;
        this.average = average;
    }

    public long time;
    public double average;
}

/**
 * A time series measurement of a metric, such as READ LATENCY.
 */
public class OneMeasurementTimeSeries extends OneMeasurement {
    /**
     * Granularity for time series; measurements will be averaged in chunks of this granularity. Units are milliseconds.
     */
    public static final String GRANULARITY = "timeseries.granularity";

    public static final String GRANULARITY_DEFAULT = "1000";

    int _granularity;
    Vector<SeriesUnit> _measurements;

    long start = -1;
    long currentunit = -1;
    int count = 0;
    int sum = 0;
    int operations = 0;
    long totallatency = 0;

    //keep a windowed version of these stats for printing status
    int windowoperations = 0;
    long windowtotallatency = 0;

    int min = -1;
    int max = -1;

    private HashMap<Integer, int[]> returncodes;

    private SummaryStatistics tputstats;

    public OneMeasurementTimeSeries(String name, Properties props) {
        super(name);
        _granularity = Integer.parseInt(props.getProperty(GRANULARITY, GRANULARITY_DEFAULT));
        _measurements = new Vector<SeriesUnit>();
        returncodes = new HashMap<Integer, int[]>();
        tputstats = new SummaryStatistics();
    }

    void checkEndOfUnit(boolean forceend) {
        long now = System.currentTimeMillis();

        if (start < 0) {
            currentunit = 0;
            start = now;
        }

        long unit = ((now - start) / _granularity) * _granularity;

        if ((unit > currentunit) || (forceend)) {
            double avg = ((double) sum) / ((double) count);
            _measurements.add(new SeriesUnit(currentunit, avg));
            //Record throughput in ops/sec for this period if there was one
            if (sum > 0) {
                tputstats.addValue(count / ((double) sum / 1000));
            }
            currentunit = unit;

            count = 0;
            sum = 0;
        }
    }

    @Override
    public void measure(int latency) {
        checkEndOfUnit(false);

        count++;
        sum += latency;
        totallatency += latency;
        operations++;
        windowoperations++;
        windowtotallatency += latency;

        if (latency > max) {
            max = latency;
        }

        if ((latency < min) || (min < 0)) {
            min = latency;
        }
    }

    @Override
    public void exportMeasurements(MeasurementsExporter exporter) throws IOException {
        checkEndOfUnit(true);

        exporter.write(getName(), "Operations", operations);
        exporter.write(getName(), "AverageLatency(us)", (((double) totallatency) / ((double) operations)));
        exporter.write(getName(), "MinLatency(us)", min);
        exporter.write(getName(), "MaxLatency(us)", max);
        exporter.write(getName(), "TputStats AverageTput", tputstats.getMean());
        exporter.write(getName(), "TputStats StdDev", tputstats.getStandardDeviation());
        exporter.write(getName(), "TputStats 95%",
                OneMeasurementStatistics.get95ConfidenceIntervalWidth(tputstats));
        exporter.write(getName(), "TputStats Intervals", tputstats.getN());

        //TODO: 95th and 99th percentile latency

        for (Integer I : returncodes.keySet()) {
            int[] val = returncodes.get(I);
            exporter.write(getName(), "Return=" + I, val[0]);
        }

        for (SeriesUnit unit : _measurements) {
            exporter.write(getName(), Long.toString(unit.time), unit.average);
        }
    }

    @Override
    public void reportReturnCode(int code) {
        Integer Icode = code;
        if (!returncodes.containsKey(Icode)) {
            int[] val = new int[1];
            val[0] = 0;
            returncodes.put(Icode, val);
        }
        returncodes.get(Icode)[0]++;

    }

    @Override
    public String getSummary() {
        if (windowoperations == 0) {
            return "";
        }
        DecimalFormat d = new DecimalFormat("#.##");
        double report = ((double) windowtotallatency) / ((double) windowoperations);
        windowtotallatency = 0;
        windowoperations = 0;
        return "[" + getName() + " AverageLatency(us)=" + d.format(report) + "]";
    }

}