public void ZeroProbabilityNeverSamplesAnyTrace()
{
var sampler = new ProbabilisticSampler(0);
Assert.False(sampler.Sample("op1", 0));
Assert.False(sampler.Sample("op2", 1));
Assert.False(sampler.Sample("op2.1", 8383));
Assert.False(sampler.Sample("op3", 89480932480));
}
public void OneProbabilitySamplesAllTraces()
{
var sampler = new ProbabilisticSampler(0.999);
Assert.True(sampler.Sample("op1", 0));
Assert.True(sampler.Sample("op2", 1));
Assert.True(sampler.Sample("op2.1", 8383));
Assert.True(sampler.Sample("op3", 89480932480));
Assert.True(sampler.Sample("op4", long.MaxValue));
}
public void TestSamplingBoundariesPositive()
{
double samplingRate = 0.5;
long halfwayBoundary = 0x3fffffffffffffffL;
ISampler sampler = new ProbabilisticSampler(samplingRate);
Assert.True(sampler.Sample("", new TraceId(halfwayBoundary)).IsSampled);
Assert.False(sampler.Sample("", new TraceId(halfwayBoundary + 2)).IsSampled);
}
public void TestSamplingBoundariesNegative()
{
double samplingRate = 0.5;
long halfwayBoundary = -0x4000000000000000L;
ISampler sampler = new ProbabilisticSampler(samplingRate);
Assert.True(sampler.Sample("", new TraceId(halfwayBoundary)).IsSampled);
Assert.False(sampler.Sample("", new TraceId(halfwayBoundary - 1)).IsSampled);
}
public void TestTags()
{
ProbabilisticSampler sampler = new ProbabilisticSampler(0.1);
var tags = sampler.Sample("vadacurry", new TraceId(20L)).Tags;
Assert.Equal("probabilistic", tags["sampler.type"]);
Assert.Equal(0.1, tags["sampler.param"]);
}
public void SamplerSetsTheCorrectTags()
{
var sampler = new ProbabilisticSampler(0.43);
var sample = sampler.Sample("an op", ulong.MinValue);
Assert.Equal("probabilistic", sample.Tags["sampler"]);
Assert.Equal(0.43.ToString(), sample.Tags["sampler-arg"]);
}
public void SamplerOnlySamplesLowerProbabilityBound(double probability)
{
var sampler = new ProbabilisticSampler(probability);
var sampled = sampler.Sample("abc", 1);
Assert.True(sampled);
var random = ulong.MaxValue * probability / 2 + 5;
Assert.True(sampler.Sample("something", (ulong)random));
var upperBound = (ulong)Math.Ceiling(ulong.MaxValue * probability);
Assert.False(sampler.Sample("upper", upperBound));
Assert.False(sampler.Sample("upper + 1", upperBound + 1));
Assert.False(sampler.Sample("upper + something", upperBound + 9894));
}
public PerOperationSamplerTests()
{
_loggerFactory = new NullLoggerFactory();
_defaultProbabilisticSampler = Substitute.ForPartsOf <ProbabilisticSampler>(0);
_undertest = new PerOperationSampler(MaxOperations, _operationToSamplers, _defaultProbabilisticSampler,
DefaultLowerBoundTracesPerSecond, _loggerFactory);
_defaultProbabilisticSampler.Sample(operation, TraceId)
.Returns(new SamplingStatus(true, EmptyTags));
_defaultProbabilisticSampler.SamplingRate.Returns(DefaultSamplingProbability);
}