Question

I am working on a project that is collecting data about performance, like the Performance Monitor does.

However, when I running a monitor on pages/sec, it is givning a different result than the Performance Monitor.
I am thinking it is because the performance counter not giving all the decimals, and the average calculation becomes inaccurate.

My code UPDATED:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Threading;
using System.Net;
using System.Management;
using System.Net.NetworkInformation;

namespace PerformanceMonitor
{
    class Program
    {

        static void Main(string[] args)
        {
       List<float> pagesSec = new List<float>();
        PerformanceCounter memoryPages = new PerformanceCounter("Memory", "Pages/sec");

        while (count < 50)
        {
            pagesSecValue = memoryPages.NextValue();
            pagesSec.Add(pagesSecValue);


           Console.WriteLine("Pages: " + pagesSecValue);
           count++;

            Thread.Sleep(1000);
            Console.Clear();
        }

Console.WriteLine("Avg pages/sec: " + pagesSec.Average());

 Console.ReadLine();
        }
}
}

While running the program, most of the time I get 0 printed on the console.

Results:
My program: 4,06349
Windows Performance Monitor: 12,133

Why the difference?

Answer 1

You’re doing different calculations than the performance counter. What you’re doing is getting the pages per second once a second for 50 seconds and getting the average of those 50 numbers. One, clearly the performance counter is working with data for a longer period of time. Two, this isn’t a useful average. The performance counter is effectively taking a much higher sample. For example, what do you think would happen if the pages per second values did this over a period of 2 seconds:
0 .5 1 1.5 2
5 15 6 20 4

And your code sampled at 0, 1 and 2 seconds? Your “average” would be 5 and the performance counter (if it sampled at .5 seconds, which it doesn’t) would be 10.