CSharp - Comparing the Performance of Sequential and Parallel Execution

  1. HOME
  2. CSharp
  3. Parallel LINQ
  4. Parallel LINQ Introduction

Introduction

We use the Stopwatch class from the System.Diagnostics namespace to measure the time that each query takes.

Demo

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;

class Program//from  ww w . j a v  a  2  s.  co  m
{
    static void Main(string[] args)
    {
        // create the sequential number range
        IEnumerable<int> numbers1 = Enumerable.Range(0, Int32.MaxValue);

        // start the stop watch
        Stopwatch sw = Stopwatch.StartNew();

        // perform the LINQ query
        int sum1 = (from n in numbers1
                    where n % 2 == 0
                    select n).Count();

        // write out the seqential result
        Console.WriteLine("Seqential result: {0}", sum1);
        // write out how long the sequential execution took
        Console.WriteLine("Sequential time: {0} ms", sw.ElapsedMilliseconds);

        // create the parallel number range
        IEnumerable<int> numbers2 = ParallelEnumerable.Range(0, Int32.MaxValue);
        // Restart the stopwatch
        sw.Restart();

        // perform the Parallel LINQ query
        int sum2 = (from n in numbers2.AsParallel()
                    where n % 2 == 0
                    select n).Count();

        // write the parallel result
        Console.WriteLine("Parallel result: {0}", sum2);
        // write out how long the parallel execution took
        Console.WriteLine("Parallel time: {0} ms", sw.ElapsedMilliseconds);
    }
}

Result

Related Topic