/// <summary>
/// Estimate Pi using TPL tasks
/// </summary>
/// <param name="maxRuntimeSeconds"></param>
/// <param name="numberOfCores"></param>
/// <remarks>This code only works with .NET 4.0 or newer</remarks>
public void TaskParallelLibrary40(int maxRuntimeSeconds, int numberOfCores)
{
var inCircleDetails = new long[numberOfCores];
var iterationDetails = new long[numberOfCores];
var tasks = new Task[numberOfCores];
var runTimesByIndex = GetRunTimesByThread(numberOfCores, maxRuntimeSeconds);
foreach (var item in runTimesByIndex)
{
// Must cache the values to avoid error "Access to modified closure"
var procIndex = item.Key;
var threadRuntime = item.Value;
tasks[procIndex] = Task.Factory.StartNew(() =>
{
var worker = new PiEstimateWorker(procIndex + 1, PreviewMode);
worker.DoWork(threadRuntime);
inCircleDetails[procIndex] = worker.HitsInCircle;
iterationDetails[procIndex] = worker.TotalIterations;
});
}
Task.WaitAll(tasks);
var inCircle = inCircleDetails.Sum();
var totalIterations = iterationDetails.Sum();
ComputeAndReportPi("TPL 4.0", inCircle, totalIterations, maxRuntimeSeconds);
}
/// <summary>
/// Estimate Pi using a parallel for loop
/// </summary>
/// <param name="maxRuntimeSeconds"></param>
/// <param name="numberOfCores"></param>
public void ParallellFor(int maxRuntimeSeconds, int numberOfCores)
{
long inCircle = 0;
long totalIterations = 0;
var threadNumber = 0;
Parallel.For(0, numberOfCores, new ParallelOptions {
MaxDegreeOfParallelism = numberOfCores
}, i =>
{
Interlocked.Add(ref threadNumber, 1);
var worker = new PiEstimateWorker(threadNumber, PreviewMode);
worker.DoWork(maxRuntimeSeconds);
Interlocked.Add(ref inCircle, worker.HitsInCircle);
Interlocked.Add(ref totalIterations, worker.TotalIterations);
if (UseTieredRuntimes)
{
maxRuntimeSeconds = DecrementRuntime(maxRuntimeSeconds, numberOfCores);
}
});
ComputeAndReportPi("ParallelFor", inCircle, totalIterations, maxRuntimeSeconds);
}
/// <summary>
/// Estimate Pi using TPL tasks
/// </summary>
/// <param name="maxRuntimeSeconds"></param>
/// <param name="numberOfCores"></param>
/// <remarks>This code only works with .NET 4.5 or newer</remarks>
public void TaskParallelLibrary45(int maxRuntimeSeconds, int numberOfCores)
{
var workers = new List <PiEstimateWorker>();
var workerTasks = new List <Task>();
var runTimesByIndex = GetRunTimesByThread(numberOfCores, maxRuntimeSeconds);
foreach (var item in runTimesByIndex)
{
// Must cache the values to avoid error "Access to modified closure"
var procIndex = item.Key;
var threadRuntime = item.Value;
var worker = new PiEstimateWorker(procIndex + 1, PreviewMode);
workers.Add(worker);
var workerTask = new Task(() => worker.DoWork(threadRuntime));
workerTasks.Add(workerTask);
workerTask.Start();
}
Task.WaitAll(workerTasks.ToArray());
var inCircle = workers.Sum(worker => worker.HitsInCircle);
var totalIterations = workers.Sum(worker => worker.TotalIterations);
ComputeAndReportPi("TPL 4.5", inCircle, totalIterations, maxRuntimeSeconds);
}
/// <summary>
/// Estimate Pi using a single thread
/// </summary>
/// <param name="maxRuntimeSeconds"></param>
public void SerialCalculation(int maxRuntimeSeconds)
{
var worker = new PiEstimateWorker(1, PreviewMode);
worker.DoWork(maxRuntimeSeconds);
ComputeAndReportPi("SerialCalculation", worker.HitsInCircle, worker.TotalIterations, maxRuntimeSeconds);
}