TPL - Parallel with Partitioner Class

Scenario:

Process data in parallel

Solution:

MSDN: Slower performance is caused by the overhead involved in partitioning the data and the cost of invoking a delegate on each loop iteration. Partitioner.Create enables sequential loop for the delegate body, so that the delegate is invoked only once per partition, instead of once per iteration.

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 public class PartitionerClassParallel
    {
        static void Main(string[] args)
        {
            var data = Enumerable.Range(0, 100).ToArray();
            var partitioner = Partitioner.Create(0, data.Length);
            var results = new double[data.Length];

            //range is to - from per partition and delegate called once per partition.
            Parallel.ForEach(partitioner, (range, loopState) =>
            {
                for (int i = range.Item1; i < range.Item2; i++)
                {
                    results[i] = data[i] * 2;
                }
            });

            foreach (var d in results)
            {
                Console.Write("{0} ", d);
            }
        }
    }