public void AdaptiveSampler_CheckNumItemsSampled()
{
SamplingParameters parameters = new SamplingParameters(this.parent, this.traceId, "test", this.activityKindServer, null, null);
AdaptiveSampler sampler = new AdaptiveSampler(5, 0.5);
int numSampled = 0;
// run for 200 seconds to let adaptive sampling adjust
for (int i = 0; i < 200; i++)
{
// sends 10 events in 1 second
int events = 10;
for (int j = 0; j < events; j++)
{
SamplingResult result = sampler.ShouldSample(parameters);
if (result.IsSampled)
{
numSampled += 1;
}
Thread.Sleep(1000 / events);
}
}
int expectedSampled = 10;
Assert.Equal(expectedSampled, numSampled / 200);
}
private static long SampleThreadTest(int maxItemsAllowed)
{
long counter = 0;
for (int j = 0; j < 200; j++)
{
for (int i = 0; i < 10; i++)
{
// System.Console.WriteLine("on span {0}", counter);
// Libraries would simply write the following lines of code to
// emit activities, which are the .NET representation of OT Spans.
var source = new ActivitySource("MyCompany.MyProduct.MyWebServer");
// The below commented out line shows more likely code in a real world webserver.
// using (var parent = source.StartActivity("HttpIn", ActivityKind.Server, HttpContext.Request.Headers["traceparent"] ))
using (var parent = source.StartActivity("HttpIn", ActivityKind.Server))
{
// counter += 1;
SamplingParameters parameters = new SamplingParameters();
SamplingResult result = Sampler.ShouldSample(parameters);
if (result.IsSampled)
{
counter++;
System.Console.WriteLine("num of items actually sampled: {0})", counter / 200);
}
// TagNames can follow the OT guidelines
// from https://github.com/open-telemetry/opentelemetry-specification/tree/master/specification/trace/semantic_conventions
parent?.AddTag("http.method", "GET");
parent?.AddTag("http.host", "MyHostName");
if (parent != null)
{
parent.DisplayName = "HttpIn DisplayName";
// IsAllDataRequested is equivalent of Span.IsRecording
if (parent.IsAllDataRequested)
{
parent.AddTag("expensive data", "This data is expensive to obtain. Avoid it if activity is not being recorded");
}
}
try
{
// Actual code to achieve the purpose of the library.
// For websebserver example, this would be calling
// user middlware pipeline.
// There can be child activities.
// In this example HttpOut is a child of HttpIn.
using (var child = source.StartActivity("HttpOut", ActivityKind.Client))
{
child?.AddTag("http.url", "www.mydependencyapi.com");
try
{
// do actual work.
child?.AddEvent(new ActivityEvent("sample activity event."));
child?.AddTag("http.status_code", "200");
}
catch (Exception)
{
child?.AddTag("http.status_code", "500");
}
}
parent?.AddTag("http.status_code", "200");
}
catch (Exception)
{
parent?.AddTag("http.status_code", "500");
}
}
Thread.Sleep(1000 / 10);
// System.Console.WriteLine("num items sampled in: {0}", Sampler.GetItemsSampled());
}
}
// System.Console.WriteLine("Spans sampled: {0}", counter);
System.Console.WriteLine("Press Enter key to exit.");
return(Sampler.GetItemsSampled());
}
