internal HistogramData(/*final*/ AbstractHistogram histogram)
{
this.histogram = histogram;
this.percentileIterator = new PercentileIterator(histogram, 1);
this.recordedValuesIterator = new RecordedValuesIterator(histogram);
this.bucketCount = histogram.bucketCount;
this.subBucketCount = histogram.subBucketCount;
}
/**
* Produce textual representation of the value distribution of histogram data by percentile. The distribution is
* output with exponentially increasing resolution, with each exponentially decreasing half-distance containing
* <i>dumpTicksPerHalf</i> percentile reporting tick points.
*
* @param printStream Stream into which the distribution will be output
* <p>
* @param percentileTicksPerHalfDistance The number of reporting points per exponentially decreasing half-distance
* <p>
* @param outputValueUnitScalingRatio The scaling factor by which to divide histogram recorded values units in
* output
* @param useCsvFormat Output in CSV format if true. Otherwise use plain text form.
*/
public void outputPercentileDistribution(/*final*/ TextWriter /*PrintStream*/ printStream,
/*final*/ int percentileTicksPerHalfDistance = 5,
/*final*/ Double outputValueUnitScalingRatio = 1000.0,
bool useCsvFormat = false)
{
if (useCsvFormat)
{
printStream.Write("\"Value\",\"Percentile\",\"TotalCount\",\"1/(1-Percentile)\"\n");
}
else
{
printStream.Write("{0,12} {1,14} {2,10} {3,14}\n\n", "Value", "Percentile", "TotalCount", "1/(1-Percentile)");
}
PercentileIterator iterator = percentileIterator;
iterator.reset(percentileTicksPerHalfDistance);
String percentileFormatString;
String lastLinePercentileFormatString;
if (useCsvFormat)
{
percentileFormatString = "{0:F" + histogram.numberOfSignificantValueDigits + "},{1:F12},{2},{3:F2}\n";
lastLinePercentileFormatString = "{0:F" + histogram.numberOfSignificantValueDigits + "},{1:F12},{2},Infinity\n";
}
else
{
percentileFormatString = "{0,12:F" + histogram.numberOfSignificantValueDigits + "}" + " {1,2:F12} {2,10} {3,14:F2}\n";
lastLinePercentileFormatString = "{0,12:F" + histogram.numberOfSignificantValueDigits + "} {1,2:F12} {2,10}\n";
}
try
{
while (iterator.hasNext())
{
HistogramIterationValue iterationValue = iterator.next();
if (iterationValue.getPercentileLevelIteratedTo() != 100.0D)
{
printStream.Write(percentileFormatString,
iterationValue.getValueIteratedTo() / outputValueUnitScalingRatio,
iterationValue.getPercentileLevelIteratedTo() / 100.0D,
iterationValue.getTotalCountToThisValue(),
1 / (1.0D - (iterationValue.getPercentileLevelIteratedTo() / 100.0D)));
}
else
{
printStream.Write(lastLinePercentileFormatString,
iterationValue.getValueIteratedTo() / outputValueUnitScalingRatio,
iterationValue.getPercentileLevelIteratedTo() / 100.0D,
iterationValue.getTotalCountToThisValue());
}
}
if (!useCsvFormat)
{
// Calculate and output mean and std. deviation.
// Note: mean/std. deviation numbers are very often completely irrelevant when
// data is extremely non-normal in distribution (e.g. in cases of strong multi-modal
// response time distribution associated with GC pauses). However, reporting these numbers
// can be very useful for contrasting with the detailed percentile distribution
// reported by outputPercentileDistribution(). It is not at all surprising to find
// percentile distributions where results fall many tens or even hundreds of standard
// deviations away from the mean - such results simply indicate that the data sampled
// exhibits a very non-normal distribution, highlighting situations for which the std.
// deviation metric is a useless indicator.
double mean = getMean() / outputValueUnitScalingRatio;
double std_deviation = getStdDeviation() / outputValueUnitScalingRatio;
printStream.Write("#[Mean = {0,12:F" + histogram.numberOfSignificantValueDigits + "}, " +
"StdDeviation = {1,12:F" + histogram.numberOfSignificantValueDigits + "}]\n", mean, std_deviation);
printStream.Write("#[Max = {0,12:F" + histogram.numberOfSignificantValueDigits + "}, Total count = {1,12}]\n",
getMaxValue() / outputValueUnitScalingRatio, getTotalCount());
printStream.Write("#[Buckets = {0,12}, SubBuckets = {1,12}]\n",
histogram.bucketCount, histogram.subBucketCount);
}
}
catch (ArgumentOutOfRangeException e)
{
// Overflow conditions on histograms can lead to ArrayIndexOutOfBoundsException on iterations:
if (histogram.hasOverflowed())
{
//printStream.format(Locale.US, "# Histogram counts indicate OVERFLOW values");
printStream.Write("# Histogram counts indicate OVERFLOW values");
}
else
{
// Re-throw if reason is not a known overflow:
throw e;
}
}
}