using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.Linq;

using System.Text;

using System.Threading;

using System.Threading.Tasks;

namespace ConsoleApplication2

{

    class Program

    {

        static void Main(string[] args)

        {

            List<int> source = new List<int>();

            for (int i = 0; i < 1000; i++)

            {

                source.Add(i);

            }

            Stopwatch stop = new Stopwatch();

            stop.Start();

            var result = (from x in source.AsParallel().WithDegreeOfParallelism(50)

                         select proc(x)).ToList();

            Console.WriteLine(stop.Elapsed);

            stop.Stop();

            Console.Read();

        }

        public static int proc(int x) {

            Thread.Sleep(100);

            return 1;

        }

    }

}