protected RollingDistributionStream(IHystrixEventStream <Event> stream, int numBuckets, int bucketSizeInMs, Func <LongHistogram, Event, LongHistogram> addValuesToBucket)
{
var emptyDistributionsToStart = new List <LongHistogram>();
for (var i = 0; i < numBuckets; i++)
{
emptyDistributionsToStart.Add(CachedValuesHistogram.GetNewHistogram());
}
Func <IObservable <Event>, IObservable <LongHistogram> > reduceBucketToSingleDistribution = (bucket) =>
{
var result = bucket.Aggregate(CachedValuesHistogram.GetNewHistogram(), (arg1, arg2) => addValuesToBucket(arg1, arg2)).Select(n => n);
return(result);
};
_rollingDistributionStream = stream
.Observe()
.Window(TimeSpan.FromMilliseconds(bucketSizeInMs), NewThreadScheduler.Default) // stream of unaggregated buckets
.SelectMany((d) => reduceBucketToSingleDistribution(d)) // stream of aggregated Histograms
.StartWith(emptyDistributionsToStart) // stream of aggregated Histograms that starts with n empty
.Window(numBuckets, 1) // windowed stream: each OnNext is a stream of n Histograms
.SelectMany((w) => ReduceWindowToSingleDistribution(w)) // reduced stream: each OnNext is a single Histogram
.Map((h) => CacheHistogramValues(h)) // convert to CachedValueHistogram (commonly-accessed values are cached)
.Publish().RefCount();
}
public int GetLatestPercentile(double percentile)
{
CachedValuesHistogram latest = Latest;
if (latest != null)
{
return(latest.GetValueAtPercentile(percentile));
}
else
{
return(0);
}
}
