static void Main()
{
// Determine how many cores/processors there are on this machine.
//
int coreCount = Environment.ProcessorCount;
Console.WriteLine("Process/core count = {0}", coreCount);
// Get some data to work with.
//
double[] data = GetData();
Stopwatch sw = Stopwatch.StartNew();
// Process the entire data set using one thread
// for comparison purposes.
//
ArrayProcessor wholeArray = new ArrayProcessor(data, 0, data.Length - 1);
wholeArray.ComputeSum();
sw.Stop();
Console.WriteLine(
"1 thread computed {0:n0} in {1:n0} ms",
wholeArray.Sum, sw.ElapsedMilliseconds
);
Console.ReadLine();
}
static void Main()
{
// Determine how many cores/processors there are on this machine.
//
int coreCount = Environment.ProcessorCount;
Console.WriteLine("Process/core count = {0}", coreCount);
// Get some data to work with.
//
double[] data = GetData();
Stopwatch sw = Stopwatch.StartNew();
// Setup same-sized arrays of references to ArraySlice
// Thread objects; one per core/processor.
//
ArrayProcessor[] slices = new ArrayProcessor[coreCount];
Thread[] threads = new Thread[coreCount];
// Divide the work (roughly) evenly among the
// number of threads we're about to start. The last
// thread will pickup any leftovers if the data size
// is not evenly divisible by the core count.
//
int indexesPerThread = data.Length / coreCount;
int leftOverIndexes = data.Length % coreCount;
for (int n = 0; n < coreCount; n++)
{
int firstIndex = (n * indexesPerThread);
int lastIndex = firstIndex + indexesPerThread - 1;
if (n == (coreCount - 1))
{
lastIndex += leftOverIndexes;
}
// Setup the array slice that describes this
// portion of the array.
//
ArrayProcessor slice = new ArrayProcessor(data, firstIndex, lastIndex);
slices[n] = slice;
// Start the thread that will process this slice.
//
threads[n] = new Thread(slice.ComputeSum);
threads[n].Start();
}
// Once all the threads have been started, wait for
// them to complete their assigned computations, then
// add their sum to the running total.
//
double sum = 0;
for (int n = 0; n < coreCount; n++)
{
threads[n].Join();
sum += slices[n].Sum;
}
sw.Stop();
// Display the results.
//
Console.WriteLine(
"{0} threads computed {1:n0} in {2:n0} ms",
coreCount, sum, sw.ElapsedMilliseconds
);
Console.ReadLine();
}
