Visual Studio Hacks [Electronic resources]

Hack 73. Access Performance Counters

Windows' performance counters can reveal all sorts of information about the inner working of your machine. Use the Server Explorer to interact with these performance counters.

The Server Explorer provides an excellent interface to access the performance counters on your computer. Using the Server Explorer, you can drag performance counters directly from the Server Explorer to your application. In this hack, you will see how to build a simple application that reads from a performance counter and reports its value to the user.

The Server Explorer includes a node called Performance Counters, which can be seen in Figure 9-1.

Each of the nodes you see in Figure 9-1 is a category that includes a number of performance counters listed beneath it. The contents of the Memory category can be seen in Figure 9-2.

From the Server Explorer, you can then drag the performance counter to your Windows Forms, and you will see the counter show up in the component section of your form, as seen in Figure 9-3.

Once the performance counter object has been added to your form, you can then access the performance counter through your code. The following code is a simple example of reading from the Available MBytes performance counter:

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Diagnostics;
namespace ServerExplorerExamples
{
public class PerfCounterExample : System.Windows.Forms.Form
{
private PerformanceCounter performanceCounter1;
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Label label2;
private System.ComponentModel.Container components = null;
public PerfCounterExample( )
{    
InitializeComponent( );
}
protected override void Dispose( bool disposing )
{
if( disposing )
{
if(components != null)
{
components.Dispose( );
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
private void InitializeComponent( )
{
this.performanceCounter1 = new PerformanceCounter( );
this.label1 = new System.Windows.Forms.Label( );
this.label2 = new System.Windows.Forms.Label( );
((System.ComponentModel.ISupportInitialize)
(this.performanceCounter1)).BeginInit( );
this.SuspendLayout( );
this.performanceCounter1.CategoryName = "Memory";
this.performanceCounter1.CounterName = "Available MBytes";
this.performanceCounter1.MachineName = "JAMESA-TABLET";
this.label1.Location = new System.Drawing.Point(8, 32);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(96, 16);
this.label1.TabIndex = 0;
this.label1.Text = "Available MBytes:";
this.label2.Location = new System.Drawing.Point(112, 32);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(100, 16);
this.label2.TabIndex = 1;
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 266);
this.Controls.Add(this.label2);
this.Controls.Add(this.label1);
this.Name = "PerfCounterExample";
this.Text = "PerfCounterExample";
this.Load += 
new System.EventHandler(this.PerfCounterExample_Load);
((System.ComponentModel.ISupportInitialize)
(this.performanceCounter1)).EndInit( );
this.ResumeLayout(false);
}
#endregion
private void PerfCounterExample_Load(
object sender, 
System.EventArgs e)
{
//Get the value of the performance counter
label2.Text = performanceCounter1.NextValue( ).ToString( );
}
}
}

When you run this code, it will produce the form shown in Figure 9-4.

9.2.1. Counter Information

You can view additional information about counters by right-clicking on a category and clicking the View Category menu item. This will display the Performance Counter Builder form (Figure 9-5), which includes a description of the category as well as a list of all the performance counters in that category. Click on a performance counter and you will be shown a description of it. This is a great way to investigate the counters in each category and what they report on.

The Server Explorer makes it easy to browse all the performance counters on your machine and then access them in your application.