public AggregateGauge()
{
var strategy = GetAggregatorStategy();
// denormalize these for one less level of indirection
_percentiles = strategy.Percentiles;
_suffixes = strategy.Suffixes;
_trackMean = strategy.TrackMean;
_specialCaseMin = strategy.SpecialCaseMin;
_specialCaseMax = strategy.SpecialCaseMax;
_specialCaseLast = strategy.SpecialCaseLast;
_reportCount = strategy.ReportCount;
// setup heap, if required.
if (strategy.UseList)
{
_list = new List <double>();
}
_snapshot = new double[_suffixes.Length];
_snapshotReportingMode = SnapshotReportingMode.None;
}
/// <summary>
/// Instantiates a new <see cref="AggregateGauge"/>.
/// </summary>
public AggregateGauge(IEnumerable <GaugeAggregator> aggregators, string name, string unit, string description, MetricSourceOptions options, ImmutableDictionary <string, string> tags = null) : base(name, unit, description, options, tags)
{
var strategy = new GaugeAggregatorStrategy(aggregators.ToImmutableArray());
// denormalize these for one less level of indirection
_percentiles = strategy.Percentiles;
_suffixes = strategy.Suffixes;
_trackMean = strategy.TrackMean;
_specialCaseMin = strategy.SpecialCaseMin;
_specialCaseMax = strategy.SpecialCaseMax;
_specialCaseLast = strategy.SpecialCaseLast;
_reportCount = strategy.ReportCount;
// setup heap, if required.
if (strategy.UseList)
{
_list = new List <double>();
}
_snapshot = new double[_suffixes.Length];
_snapshotReportingMode = SnapshotReportingMode.None;
}
private void CaptureSnapshot()
{
List <double> list = null;
double last;
double min;
double max;
int count;
double sum;
lock (_recordLock)
{
if (_count > 0)
{
list = _list;
if (list != null)
{
#if DEBUG
if (_warmlist != null)
{
Debug.WriteLine("BosunReporter: Re-using pre-warmed list for aggregate gauge.");
}
#endif
_list = _warmlist ?? new List <double>();
_warmlist = null;
}
}
last = _last;
min = _min;
_min = Double.PositiveInfinity;
max = _max;
_max = Double.NegativeInfinity;
sum = _sum;
_sum = 0;
count = _count;
_count = 0;
}
if (count == 0 || count < MinimumEvents)
{
_snapshotReportingMode = _reportCount ? SnapshotReportingMode.CountOnly : SnapshotReportingMode.None;
}
else
{
_snapshotReportingMode = SnapshotReportingMode.All;
}
if (_snapshotReportingMode != SnapshotReportingMode.None)
{
var countOnly = _snapshotReportingMode == SnapshotReportingMode.CountOnly;
var lastIndex = 0;
if (!countOnly && list != null)
{
lastIndex = list.Count - 1;
if (!_specialCaseLast)
{
last = list[lastIndex];
}
list.Sort();
}
for (var i = 0; i < _percentiles.Length; i++)
{
var mode = PercentileToAggregateMode(_percentiles[i]);
if (countOnly && mode != AggregateMode.Count)
{
continue;
}
double value;
switch (mode)
{
case AggregateMode.Average:
value = sum / count;
break;
case AggregateMode.Median:
case AggregateMode.Percentile:
var index = (int)Math.Round(_percentiles[i] * lastIndex);
value = list[index];
break;
case AggregateMode.Max:
value = _specialCaseMax ? max : list[lastIndex];
break;
case AggregateMode.Min:
value = _specialCaseMin ? min : list[0];
break;
case AggregateMode.Last:
value = last;
break;
case AggregateMode.Count:
value = count;
break;
default:
throw new NotImplementedException();
}
_snapshot[i] = value;
}
}
if (list != null && list.Count * 2 >= list.Capacity)
{
// if at least half of the list capacity was used, then we'll consider re-using this list.
list.Clear();
lock (_recordLock)
{
_warmlist = list;
}
}
}
