Examples with Histogram org.HdrHistogram.Histogram used on opensource projects

Example 21 with Histogram

use of org.HdrHistogram.Histogram in project grpc-java by grpc.

the class AsyncClient method run.

/**
   * Start the QPS Client.
   */
public void run() throws Exception {
    if (config == null) {
        return;
    }
    SimpleRequest req = newRequest();
    List<ManagedChannel> channels = new ArrayList<ManagedChannel>(config.channels);
    for (int i = 0; i < config.channels; i++) {
        channels.add(config.newChannel());
    }
    // Do a warmup first. It's the same as the actual benchmark, except that
    // we ignore the statistics.
    warmup(req, channels);
    long startTime = System.nanoTime();
    long endTime = startTime + TimeUnit.SECONDS.toNanos(config.duration);
    List<Histogram> histograms = doBenchmark(req, channels, endTime);
    long elapsedTime = System.nanoTime() - startTime;
    Histogram merged = merge(histograms);
    printStats(merged, elapsedTime);
    if (config.histogramFile != null) {
        saveHistogram(merged, config.histogramFile);
    }
    shutdown(channels);
}

Example 22 with Histogram

use of org.HdrHistogram.Histogram in project grpc-java by grpc.

the class OpenLoopClient method run.

/**
   * Start the open loop client.
   */
public void run() throws Exception {
    if (config == null) {
        return;
    }
    config.channels = 1;
    config.directExecutor = true;
    ManagedChannel ch = config.newChannel();
    SimpleRequest req = config.newRequest();
    LoadGenerationWorker worker = new LoadGenerationWorker(ch, req, config.targetQps, config.duration);
    final long start = System.nanoTime();
    Histogram histogram = worker.call();
    final long end = System.nanoTime();
    printStats(histogram, end - start);
    if (config.histogramFile != null) {
        saveHistogram(histogram, config.histogramFile);
    }
    ch.shutdown();
}

Example 23 with Histogram

use of org.HdrHistogram.Histogram in project grpc-java by grpc.

the class LoadClient method getStats.

/**
   * Take a snapshot of the statistics which can be returned to the driver.
   */
Stats.ClientStats getStats() {
    Histogram intervalHistogram = recorder.getIntervalHistogram();
    Stats.ClientStats.Builder statsBuilder = Stats.ClientStats.newBuilder();
    Stats.HistogramData.Builder latenciesBuilder = statsBuilder.getLatenciesBuilder();
    double resolution = 1.0 + Math.max(config.getHistogramParams().getResolution(), 0.01);
    LogarithmicIterator logIterator = new LogarithmicIterator(intervalHistogram, 1, resolution);
    double base = 1;
    while (logIterator.hasNext()) {
        latenciesBuilder.addBucket((int) logIterator.next().getCountAddedInThisIterationStep());
        base = base * resolution;
    }
    // have values.
    while (base < config.getHistogramParams().getMaxPossible()) {
        latenciesBuilder.addBucket(0);
        base = base * resolution;
    }
    latenciesBuilder.setMaxSeen(intervalHistogram.getMaxValue());
    latenciesBuilder.setMinSeen(intervalHistogram.getMinNonZeroValue());
    latenciesBuilder.setCount(intervalHistogram.getTotalCount());
    latenciesBuilder.setSum(intervalHistogram.getMean() * intervalHistogram.getTotalCount());
    // TODO: No support for sum of squares
    statsBuilder.setTimeElapsed((intervalHistogram.getEndTimeStamp() - intervalHistogram.getStartTimeStamp()) / 1000.0);
    if (osBean != null) {
        // Report all the CPU time as user-time  (which is intentionally incorrect)
        long nowCpu = osBean.getProcessCpuTime();
        statsBuilder.setTimeUser(((double) nowCpu - lastMarkCpuTime) / 1000000000.0);
        lastMarkCpuTime = nowCpu;
    }
    return statsBuilder.build();
}

Example 24 with Histogram

use of org.HdrHistogram.Histogram in project grpc-java by grpc.

the class AsyncClient method merge.

private static Histogram merge(List<Histogram> histograms) {
    Histogram merged = new Histogram(HISTOGRAM_MAX_VALUE, HISTOGRAM_PRECISION);
    for (Histogram histogram : histograms) {
        for (HistogramIterationValue value : histogram.allValues()) {
            long latency = value.getValueIteratedTo();
            long count = value.getCountAtValueIteratedTo();
            merged.recordValueWithCount(latency, count);
        }
    }
    return merged;
}

Example 25 with Histogram

use of org.HdrHistogram.Histogram in project hazelcast by hazelcast.

the class HyperLogLogEncoderAbstractTest method testEstimateErrorRateForBigCardinalities.

/**
     * - Add up-to runLength() random numbers on both a Set and a HyperLogLog encoder.
     * - Sample the actual count, and the estimate respectively every 100 operations.
     * - Compute the error rate, of the measurements and store it in a histogram.
     * - Assert that the 99th percentile of the histogram is less than the expected max error,
     * which is the result of std error (1.04 / sqrt(m)) + 3%.
     * (2% is the typical accuracy, but tests on the implementation showed up rare occurrences of 3%)
     */
@Test
public void testEstimateErrorRateForBigCardinalities() {
    double stdError = (1.04 / Math.sqrt(1 << precision())) * 100;
    double maxError = Math.ceil(stdError + 3.0);
    IntHashSet actualCount = new IntHashSet(runLength(), -1);
    Random random = new Random();
    Histogram histogram = new Histogram(5);
    ByteBuffer bb = ByteBuffer.allocate(4);
    int sampleStep = 100;
    long expected;
    long actual;
    for (int i = 1; i <= runLength(); i++) {
        int toCount = random.nextInt();
        actualCount.add(toCount);
        bb.clear();
        bb.putInt(toCount);
        encoder.add(HashUtil.MurmurHash3_x64_64(bb.array(), 0, bb.array().length));
        if (i % sampleStep == 0) {
            expected = actualCount.size();
            actual = encoder.estimate();
            double errorPct = ((actual * 100.0) / expected) - 100;
            histogram.recordValue(Math.abs((long) (errorPct * 100)));
        }
    }
    double errorPerc99 = histogram.getValueAtPercentile(99) / 100.0;
    if (errorPerc99 > maxError) {
        fail("For P=" + precision() + ", max error=" + maxError + "% expected." + " Error: " + errorPerc99 + "%.");
    }
}