public void CanTrace_StressTest()
{
// Create a rate limiter that allows .5 QPS
var rateLimiter = new RateLimiter(.5, StopwatchTimer.Create());
int canTraceCounter = 0;
DateTime start = DateTime.UtcNow;
DateTime end = start.AddSeconds(5.5);
// Create 10 threads to run for a little over five seconds.
var threads = Enumerable.Range(0, 10)
.Select(_ => new Thread(() =>
{
while (DateTime.UtcNow < end)
{
// Avoid completely tight-looping, so that we can actually start enough threads.
// (Note that Thread.Yield isn't available on .NET Core.)
Thread.Sleep(1);
if (rateLimiter.CanTrace())
{
Interlocked.Increment(ref canTraceCounter);
}
}
}))
.ToList();
// Start the threads and wait for them all to finish
threads.ForEach(t => t.Start());
threads.ForEach(t => t.Join());
// We should have exactly 3 traces: one at t~=0, one at t~=2, one at t~=4.
// (The test machine would have to be very highly loaded to take half a second between
// the check in the while loop and the increment leading to an over-count, and it would have
// to take half a second to start the threads to lead to an under-count.)
Assert.Equal(3, canTraceCounter);
}
public void CanTrace_Always_StressTest()
{
// Create a rate limiter that allows 1_000_000 QPS, which effectively means can trace always.
var rateLimiter = new RateLimiter(1_000_000, StopwatchTimer.Create());
int canTraceCounter = 0;
int canTraceQuestions = 0;
DateTime start = DateTime.UtcNow;
DateTime end = start.AddSeconds(5.5);
// Create 10 threads to run for a little over five seconds.
var threads = Enumerable.Range(0, 10)
.Select(_ => new Thread(() =>
{
while (DateTime.UtcNow < end)
{
// Avoid completely tight-looping, so that we can actually start enough threads.
// (Note that Thread.Yield isn't available on .NET Core.)
Thread.Sleep(1);
Interlocked.Increment(ref canTraceQuestions);
if (rateLimiter.CanTrace())
{
Interlocked.Increment(ref canTraceCounter);
}
}
}))
.ToList();
// Start the threads and wait for them all to finish
threads.ForEach(t => t.Start());
threads.ForEach(t => t.Join());
// Since everything is to be traced, we should have as many traces as we attempted.
Assert.Equal(canTraceQuestions, canTraceCounter);
}
public void CanTrace_StressTest()
{
// Create a rate limiter that allows 1 QPS
var rateLimiter = new RateLimiter(1, StopwatchTimer.Create());
int canTraceCounter = 0;
DateTime start = DateTime.UtcNow;
DateTime end = start.AddSeconds(2.5);
// Create 10 threads to run for a little over two seconds.
var threads = Enumerable.Range(0, 10)
.Select(_ => new Thread(() =>
{
while (DateTime.UtcNow < end)
{
if (rateLimiter.CanTrace())
{
Interlocked.Increment(ref canTraceCounter);
}
}
}))
.ToList();
// Start the threads and wait for them all to finish
threads.ForEach(t => t.Start());
threads.ForEach(t => t.Join());
// We should have exactly 3 traces: one at t~=0, one at t~=1, one at t~=2.
// (The test machine would have to be very highly loaded to take half a second between
// the check in the while loop and the increment leading to an over-count, and it would have
// to take half a second to start the threads to lead to an under-count.)
Assert.Equal(3, canTraceCounter);
}
public void GetElapsedMilliseconds_NoStart()
{
StopwatchTimer timer = StopwatchTimer.Create();
Assert.Equal(0, timer.GetElapsedMilliseconds());
Thread.Sleep(10);
Assert.Equal(0, timer.GetElapsedMilliseconds());
}
public void GetElapsedMilliseconds()
{
StopwatchTimer timer = StopwatchTimer.Create();
timer.Start();
long first = timer.GetElapsedMilliseconds();
Thread.Sleep(10);
long second = timer.GetElapsedMilliseconds();
Thread.Sleep(20);
long third = timer.GetElapsedMilliseconds();
Assert.True(second > first);
Assert.True(third > second);
}