Helpers for BenchmarkDotNet.
Useful for benchmarking actions ran on multiple threads concurrently more accurately than other solutions.
It can be the same action ran multiple times in parallel, like incrementing a counter. Or it can be different actions ran at the same time in parallel, like reading from and writing to a concurrent collection.
Example, to compare the performance of incrementing a counter using Interlocked vs with a lock:
public class ThreadBenchmarks
{
private BenchmarkThreadHelper threadHelper;
private readonly object locker = new();
private int counter;
[GlobalCleanup]
public void Cleanup()
{
threadHelper.Dispose();
}
[GlobalSetup(Target = nameof(ThreadHelperInterlocked))]
public void SetupInterlocked()
{
Action action = () => Interlocked.Increment(ref counter);
threadHelper = new BenchmarkThreadHelper()
{
action,
action,
action,
action
};
}
[Benchmark]
public void ThreadHelperInterlocked()
{
threadHelper.ExecuteAndWait();
}
[GlobalSetup(Target = nameof(ThreadHelperLocked))]
public void SetupLocked()
{
Action action = () =>
{
unchecked
{
lock (locker)
{
++counter;
}
}
};
threadHelper = new BenchmarkThreadHelper()
{
action,
action,
action,
action
};
}
[Benchmark]
public void ThreadHelperLocked()
{
threadHelper.ExecuteAndWait();
}
}Compare to System.Threading.Tasks.Parallel:
| Method | MaxConcurrency | Mean | Error | StdDev | Allocated |
|---|---|---|---|---|---|
| ParallelOverhead | -1 | 4,086.4 ns | 78.81 ns | 80.93 ns | 514 B |
| ParallelInterlocked | -1 | 4,370.0 ns | 86.95 ns | 147.65 ns | 517 B |
| ParallelLocked | -1 | 4,798.6 ns | 54.14 ns | 50.64 ns | 522 B |
| ThreadHelperOverhead | -1 | 1,172.7 ns | 3.55 ns | 3.32 ns | - |
| ThreadHelperInterlocked | -1 | 1,302.8 ns | 2.07 ns | 1.83 ns | - |
| ThreadHelperLocked | -1 | 1,660.2 ns | 4.42 ns | 4.13 ns | - |
| ParallelOverhead | 2 | 2,843.1 ns | 19.03 ns | 17.80 ns | 1288 B |
| ParallelInterlocked | 2 | 2,737.6 ns | 20.99 ns | 19.63 ns | 1288 B |
| ParallelLocked | 2 | 2,805.0 ns | 18.68 ns | 17.48 ns | 1288 B |
| ThreadHelperOverhead | 2 | 602.1 ns | 2.39 ns | 2.23 ns | - |
| ThreadHelperInterlocked | 2 | 697.4 ns | 2.77 ns | 2.59 ns | - |
| ThreadHelperLocked | 2 | 992.7 ns | 2.93 ns | 2.74 ns | - |
Very similar to BenchmarkThreadHelper, except AsyncBenchmarkThreadHelper supports async actions.
public class ThreadAsyncBenchmarks
{
private const int numTasks = 2;
[ParamsAllValues]
public bool Yield { get; set; }
private AsyncBenchmarkThreadHelper asyncThreadHelper;
private async ValueTask FuncAsync()
{
if (Yield)
await Task.Yield();
}
[GlobalSetup(Target = nameof(AsyncThreadHelper))]
public void SetupAsyncThreadHelper()
{
asyncThreadHelper = new();
for (int i = 0; i < numTasks; ++i)
{
asyncThreadHelper.Add(() => FuncAsync());
}
}
[Benchmark]
public ValueTask AsyncThreadHelper()
{
return asyncThreadHelper.ExecuteAndWaitAsync();
}
}Compare to Task.Run and Task.WhenAll:
| Method | Yield | Mean | Error | StdDev | Allocated |
|---|---|---|---|---|---|
| TaskRun | False | 3,568.3 ns | 17.02 ns | 15.92 ns | 408 B |
| AsyncThreadHelper | False | 833.6 ns | 2.97 ns | 2.48 ns | - |
| TaskRun | True | 5,769.1 ns | 109.06 ns | 112.00 ns | 648 B |
| AsyncThreadHelper | True | 3,666.5 ns | 10.15 ns | 9.00 ns | 240 B |