public GetPercentile ( double percentile ) : int | ||
percentile | double | |
return | int |
public void testRolling() { MockedClock time = new MockedClock(); RollingPercentileNumber p = new RollingPercentileNumber(time, timeInMilliseconds, numberOfBuckets, bucketDataLength, DynamicProperties.Factory.AsProperty(true)); p.AddValue(1000); p.AddValue(1000); p.AddValue(1000); p.AddValue(2000); Assert.Equal(1, p.GetBuckets().Count()); // no bucket turnover yet so percentile not yet generated Assert.Equal(0, p.GetPercentile(50)); time.Increment(6000); // still only 1 bucket until we touch it again Assert.Equal(1, p.GetBuckets().Count()); // a bucket has been created so we have a new percentile Assert.Equal(1000, p.GetPercentile(50)); // now 2 buckets since getting a percentile causes bucket retrieval Assert.Equal(2, p.GetBuckets().Count()); p.AddValue(1000); p.AddValue(500); // should still be 2 buckets Assert.Equal(2, p.GetBuckets().Count()); p.AddValue(200); p.AddValue(200); p.AddValue(1600); p.AddValue(200); p.AddValue(1600); p.AddValue(1600); // we haven't progressed to a new bucket so the percentile should be the same and ignore the most recent bucket Assert.Equal(1000, p.GetPercentile(50)); // Increment to another bucket so we include all of the above in the PercentileSnapshot time.Increment(6000); // the rolling version should have the same data as creating a snapshot like this PercentileSnapshot ps = new PercentileSnapshot(1000, 1000, 1000, 2000, 1000, 500, 200, 200, 1600, 200, 1600, 1600); Assert.Equal(ps.GetPercentile(0.15), p.GetPercentile(0.15)); Assert.Equal(ps.GetPercentile(0.50), p.GetPercentile(0.50)); Assert.Equal(ps.GetPercentile(0.90), p.GetPercentile(0.90)); Assert.Equal(ps.GetPercentile(0.995), p.GetPercentile(0.995)); //Console.WriteLine("100th: " + ps.GetPercentile(100) + " " + p.GetPercentile(100)); //Console.WriteLine("99.5th: " + ps.GetPercentile(99.5) + " " + p.GetPercentile(99.5)); //Console.WriteLine("99th: " + ps.GetPercentile(99) + " " + p.GetPercentile(99)); //Console.WriteLine("90th: " + ps.GetPercentile(90) + " " + p.GetPercentile(90)); //Console.WriteLine("50th: " + ps.GetPercentile(50) + " " + p.GetPercentile(50)); //Console.WriteLine("10th: " + ps.GetPercentile(10) + " " + p.GetPercentile(10)); // mean = 1000+1000+1000+2000+1000+500+200+200+1600+200+1600+1600/12 Assert.Equal(991, ps.Mean); }
public void testThreadSafety() { MockedClock time = new MockedClock(); RollingPercentileNumber p = new RollingPercentileNumber(time, 100, 25, 1000, DynamicProperties.Factory.AsProperty(true)); int NUM_THREADS = 1000; int NUM_ITERATIONS = 1000000; var tasks = new Task [NUM_THREADS]; long aggregateMetrics = 0; //same as a blackhole Random r = new Random(); var token = new CancellationTokenSource(); var metricsPoller = Task.Run(() => { while (!token.IsCancellationRequested) { Interlocked.Add(ref aggregateMetrics, p.Mean + p.GetPercentile(10) + p.GetPercentile(50) + p.GetPercentile(90)); //Console.WriteLine("AGGREGATE : " + p.GetPercentile(10) + " : " + p.GetPercentile(50) + " : " + p.GetPercentile(90)); } }); for (int i = 0; i < NUM_THREADS; i++) { int threadId = i; tasks[i] = Task.Run(() => { for (int j = 1; j < NUM_ITERATIONS / NUM_THREADS + 1; j++) { int nextInt = r.Next(100); p.AddValue(nextInt); if (threadId == 0) { time.Increment(1); } } }); } if( !Task.WaitAll(tasks, 1000)) throw new Exception("Timeout on all threads writing percentiles"); token.Cancel(); Interlocked.Add(ref aggregateMetrics, p.Mean + p.GetPercentile(10) + p.GetPercentile(50) + p.GetPercentile(90)); //Console.WriteLine(p.Mean + " : " + p.GetPercentile(50) + " : " + p.GetPercentile(75) + " : " + p.GetPercentile(90) + " : " + p.GetPercentile(95) + " : " + p.GetPercentile(99)); }
public void testSampleDataOverTime1() { //Console.WriteLine("\n\n***************************** testSampleDataOverTime1 \n"); MockedClock time = new MockedClock(); RollingPercentileNumber p = new RollingPercentileNumber(time, timeInMilliseconds, numberOfBuckets, bucketDataLength, DynamicProperties.Factory.AsProperty(true)); int previousTime = 0; for (int i = 0; i < SampleDataHolder1.data.Length/2; i++) { int timeInMillisecondsSinceStart = SampleDataHolder1.data[i,0]; int latency = SampleDataHolder1.data[i,1]; time.Increment(timeInMillisecondsSinceStart - previousTime); previousTime = timeInMillisecondsSinceStart; p.AddValue(latency); } //Console.WriteLine("0.01: " + p.GetPercentile(0.01)); //Console.WriteLine("Median: " + p.GetPercentile(50)); //Console.WriteLine("90th: " + p.GetPercentile(90)); //Console.WriteLine("99th: " + p.GetPercentile(99)); //Console.WriteLine("99.5th: " + p.GetPercentile(99.5)); //Console.WriteLine("99.99: " + p.GetPercentile(99.99)); //Console.WriteLine("Median: " + p.GetPercentile(50)); //Console.WriteLine("Median: " + p.GetPercentile(50)); //Console.WriteLine("Median: " + p.GetPercentile(50)); /* * In a loop as a use case was found where very different values were calculated in subsequent requests. */ for (int i = 0; i < 10; i++) { if (p.GetPercentile(50) > 5) { throw new Exception("We expect around 2 but got: " + p.GetPercentile(50)); } if (p.GetPercentile(99.5) < 20) { throw new Exception("We expect to see some high values over 20 but got: " + p.GetPercentile(99.5)); } } }
public void testSampleDataOverTime2() { //Console.WriteLine("\n\n***************************** testSampleDataOverTime2 \n"); MockedClock time = new MockedClock(); int previousTime = 0; RollingPercentileNumber p = new RollingPercentileNumber(time, timeInMilliseconds, numberOfBuckets, bucketDataLength, DynamicProperties.Factory.AsProperty(true)); for (int i = 0; i < SampleDataHolder2.data.Length/2; i++) { int timeInMillisecondsSinceStart = SampleDataHolder2.data[i,0]; int latency = SampleDataHolder2.data[i,1]; time.Increment(timeInMillisecondsSinceStart - previousTime); previousTime = timeInMillisecondsSinceStart; p.AddValue(latency); } //Console.WriteLine("0.01: " + p.GetPercentile(0.01)); //Console.WriteLine("Median: " + p.GetPercentile(50)); //Console.WriteLine("90th: " + p.GetPercentile(90)); //Console.WriteLine("99th: " + p.GetPercentile(99)); //Console.WriteLine("99.5th: " + p.GetPercentile(99.5)); //Console.WriteLine("99.99: " + p.GetPercentile(99.99)); if (p.GetPercentile(50) > 90 || p.GetPercentile(50) < 50) { throw new Exception("We expect around 60-70 but got: " + p.GetPercentile(50)); } if (p.GetPercentile(99) < 400) { throw new Exception("We expect to see some high values over 400 but got: " + p.GetPercentile(99)); } }
public void testValueIsZeroAfterRollingWindowPassesAndNoTraffic() { MockedClock time = new MockedClock(); var p = new RollingPercentileNumber(time, timeInMilliseconds, numberOfBuckets, bucketDataLength, DynamicProperties.Factory.AsProperty(true)); p.AddValue(1000); p.AddValue(1000); p.AddValue(1000); p.AddValue(2000); p.AddValue(4000); Assert.Equal(1, p.GetBuckets().Count()); // no bucket turnover yet so percentile not yet generated Assert.Equal(0, p.GetPercentile(50)); time.Increment(6000); // still only 1 bucket until we touch it again Assert.Equal(1, p.GetBuckets().Count()); // a bucket has been created so we have a new percentile Assert.Equal(1500, p.GetPercentile(50)); // let 1 minute pass time.Increment(60000); // no data in a minute should mean all buckets are empty (or reset) so we should not have any percentiles Assert.Equal(0, p.GetPercentile(50)); }