PerformanceCounter, classe

using System;
using System.Collections;
using System.Collections.Specialized;
using System.Diagnostics;

public class App {

	private static PerformanceCounter PC;
	private static PerformanceCounter BPC;

	public static void Main()
	{	
	
		ArrayList samplesList = new ArrayList();

        // If the category does not exist, create the category and exit.
        // Performance counters should not be created and immediately used.
        // There is a latency time to enable the counters, they should be created
        // prior to executing the application that uses the counters.
        // Execute this sample a second time to use the category.
        if (SetupCategory())
            return;
		CreateCounters();
		CollectSamples(samplesList);
		CalculateResults(samplesList);

	}
	

	private static bool SetupCategory()
	{		
		if ( !PerformanceCounterCategory.Exists("AverageCounter64SampleCategory") ) 
		{

			CounterCreationDataCollection CCDC = new CounterCreationDataCollection();
			
			// Add the counter.
			CounterCreationData averageCount64 = new CounterCreationData();
			averageCount64.CounterType = PerformanceCounterType.AverageCount64;
			averageCount64.CounterName = "AverageCounter64Sample";
			CCDC.Add(averageCount64);
	        
	        // Add the base counter.
			CounterCreationData averageCount64Base = new CounterCreationData();
			averageCount64Base.CounterType = PerformanceCounterType.AverageBase;
			averageCount64Base.CounterName = "AverageCounter64SampleBase";
			CCDC.Add(averageCount64Base);

			// Create the category.
			PerformanceCounterCategory.Create("AverageCounter64SampleCategory",
                "Demonstrates usage of the AverageCounter64 performance counter type.",
                PerformanceCounterCategoryType.SingleInstance, CCDC);
				
			return(true);
		}
		else
		{
			Console.WriteLine("Category exists - AverageCounter64SampleCategory");
			return(false);
		}
	}
	
	private static void CreateCounters()
	{
		// Create the counters.

		PC = new PerformanceCounter("AverageCounter64SampleCategory", 
			"AverageCounter64Sample", 
			false);
		

		BPC = new PerformanceCounter("AverageCounter64SampleCategory", 
			"AverageCounter64SampleBase", 
			false);
		
		
		PC.RawValue=0;
		BPC.RawValue=0;
	}
	private static void CollectSamples(ArrayList samplesList)
	{
		
		Random r = new Random( DateTime.Now.Millisecond );

		// Loop for the samples.
		for (int j = 0; j < 100; j++) 
		{
	        
			int value = r.Next(1, 10);
			Console.Write(j + " = " + value);

			PC.IncrementBy(value);

			BPC.Increment();

			if ((j % 10) == 9) 
			{
				OutputSample(PC.NextSample());
				samplesList.Add( PC.NextSample() );
			}
			else
				Console.WriteLine();
	        
			System.Threading.Thread.Sleep(50);
		}

	}
	
	private static void CalculateResults(ArrayList samplesList)
	{
		for(int i = 0; i < (samplesList.Count - 1); i++)
		{
			// Output the sample.
			OutputSample( (CounterSample)samplesList[i] );
			OutputSample( (CounterSample)samplesList[i+1] );

			// Use .NET to calculate the counter value.
			Console.WriteLine(".NET computed counter value = " +
				CounterSampleCalculator.ComputeCounterValue((CounterSample)samplesList[i],
				(CounterSample)samplesList[i+1]) );

			// Calculate the counter value manually.
			Console.WriteLine("My computed counter value = " + 
				MyComputeCounterValue((CounterSample)samplesList[i],
				(CounterSample)samplesList[i+1]) );

		}
	}
	
	
	//++++++++//++++++++//++++++++//++++++++//++++++++//++++++++//++++++++//++++++++
	//	Description - This counter type shows how many items are processed, on average,
	//		during an operation. Counters of this type display a ratio of the items 
	//		processed (such as bytes sent) to the number of operations completed. The  
	//		ratio is calculated by comparing the number of items processed during the 
	//		last interval to the number of operations completed during the last interval. 
	// Generic type - Average
	//  	Formula - (N1 - N0) / (D1 - D0), where the numerator (N) represents the number 
	//		of items processed during the last sample interval and the denominator (D) 
	//		represents the number of operations completed during the last two sample 
	//		intervals. 
	//	Average (Nx - N0) / (Dx - D0)  
	//	Example PhysicalDisk\ Avg. Disk Bytes/Transfer 
	//++++++++//++++++++//++++++++//++++++++//++++++++//++++++++//++++++++//++++++++
	private static Single MyComputeCounterValue(CounterSample s0, CounterSample s1)
	{
		Single numerator = (Single)s1.RawValue - (Single)s0.RawValue;
		Single denomenator = (Single)s1.BaseValue - (Single)s0.BaseValue;
		Single counterValue = numerator / denomenator;
		return(counterValue);
	}
		
	// Output information about the counter sample.
	private static void OutputSample(CounterSample s)
	{
		Console.WriteLine("\r\n+++++++++++");
		Console.WriteLine("Sample values - \r\n");
		Console.WriteLine("   BaseValue        = " + s.BaseValue);
		Console.WriteLine("   CounterFrequency = " + s.CounterFrequency);
		Console.WriteLine("   CounterTimeStamp = " + s.CounterTimeStamp);
		Console.WriteLine("   CounterType      = " + s.CounterType);
		Console.WriteLine("   RawValue         = " + s.RawValue);
		Console.WriteLine("   SystemFrequency  = " + s.SystemFrequency);
		Console.WriteLine("   TimeStamp        = " + s.TimeStamp);
		Console.WriteLine("   TimeStamp100nSec = " + s.TimeStamp100nSec);
		Console.WriteLine("++++++++++++++++++++++");
	}
}