C# 4 and .NET 4

484 ❘ ChaPTer 19 instrumentAtiOn
Performance Counter builder
The sample application PerformanceCounterDemo is
a simple Windows application with just two buttons
to demonstrate writing performance counts. With
the handler of one button, a performance counter
category is registered; with the handler of the other
button, a performance counter value is written. In a
similar way to the sample application, you can add
performance counters to a Windows Service (see
Chapter 25, “ Windows Services ” ), to a network
application (see Chapter 24, “ Networking ” ), or to
any other application from that you would like to
receive live counts.
Using Visual Studio, you can create a new
performance counter category by selecting the
performance counters in the Server Explorer and by
selecting the menu entry Create New Category on
the context menu. This launches the Performance
Counter Builder (see Figure 19 - 7).
figure 19-7
To create a performance counter category with Visual Studio, Visual Studio must be
started in elevated mode.
Set the name of the performance counter category to Wrox Performance Counters . The following table
shows all performance counters of the quote service.
name desCriPTion T y P e
# of button clicks Total # of button clicks NumberOfItems32
# of button clicks/sec # of button clicks in one second RateOfCountsPerSecond32
# of mouse move events Total # of mouse move events NumberOfItems32
# of mouse move events/sec # of mouse move events in one second RateOfCountsPerSecond32
The Performance Counter Builder writes the confi guration to the performance database. This can also
be done dynamically by using the Create() method of the PerformanceCounterCategory class in the
System.Diagnostics namespace. An installer for other systems can easily be added later using Visual
Studio.
The following code snippet shows how a performance category can be added programmatically.
With the tool from Visual Studio, you can only create a global performance category that doesn ’ t
have different values for different processes of running applications. Creating a performance category
programmatically allows you to monitor performance counts from different applications, which is also
done here.
First, a const for the category name is defi ned, as well as SortedList < TKey, TValue > , which contains the
names of the performance counts:
private const string perfomanceCounterCategoryName = "Wrox Performance Counters";
private SortedList < string, Tuple < string, string > > perfCountNames;
code snippet PerformanceCounterDemo/MainWindow.xaml.cs
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