public void Returns_Average()
{
var metric = new AverageMetric();
metric.Report(1);
metric.Report(3);
Assert.AreEqual(2, metric.Average);
}
public async Task Returns_AverageAsync()
{
var metric = new AverageMetric();
var readers = new List <Task>();
var tasks = new List <Task>();
for (int i = 0; i < 10000; ++i)
{
tasks.Add(Task.Run(() => metric.Report(2)));
if (i % 10 == 0)
{
readers.Add(Task.Run(() => Assert.AreEqual(2, metric.Average)));
}
}
await Task.WhenAll(tasks);
Assert.AreEqual(2, metric.Average);
await Task.WhenAll(readers);
}
public void Eventually_returns_value_when_multiple_threads()
{
const int threadCount = 8;
const int spinCount = 1000_000;
var threads = new Thread[threadCount];
var wait = new ManualResetEvent(false);
var metric = new AverageMetric();
for (var i = 0; i < threadCount; i++)
{
var threadNo = i;
threads[i] = new Thread(() =>
{
wait.WaitOne();
for (var j = 0; j < spinCount; j++)
{
metric.Report(threadNo % 2); // report 0 or 1
}
});
}
foreach (var thread in threads)
{
thread.Start();
}
wait.Set();
foreach (var thread in threads)
{
thread.Join();
}
Assert.AreEqual(0.5d, metric.Average);
}
public async Task Returns_Average_MultiThreaded()
{
const int iterations = 100000;
var metric = new AverageMetric();
var t1 = Task.Run(async() =>
{
await Task.Delay(1000);
for (int i = 0; i < iterations; i++)
{
metric.Report(1);
}
});
var t2 = Task.Run(async() =>
{
await Task.Delay(1000);
for (int i = 0; i < iterations; i++)
{
metric.Report(3);
}
});
await Task.WhenAll(t1, t2);
Assert.AreEqual(2, metric.Average);
}
