You are developing a method named CreateCounters that will create performance counters for an
application. The method includes the following code. (Line numbers are included for reference only.)
01 void CreateCounters()
02 {
03 if (!PerformanceCounterCategory.Exists(“Contoso”))
04 {
05 var counters = new CounterCreationDataCollection();
06 var ccdCounter1 = new CounterCreationData
07 {
08 CounterName = “Counter1”,
09 CounterType = PerformanceCounterType.SampleFraction
11 };
12 counters.Add(ccdCounter1);
13 var ccdCounter2 = new CounterCreationData
14 {
15 CounterName = “Counter2”,
16
17 };
18 counters.Add(ccdCounter2);
19 PerformanceCounterCategory.Create(“Contoso”, “Help string”,20 PerformanceCounterCategoryType.MultiInstance, counters);
21 }
22 }
You need to ensure that Counter1 is available for use in Windows Performance Monitor (PerfMon). Which
code segment should you insert at line 16?

A.
CounterType = PerformanceCounterType.RawBase;

B.
CounterType = PerformanceCounterType.AverageBase;

C.
CounterType = PerformanceCounterType.SampleBase;

D.
CounterType = PerformanceCounterType.CounterMultiBase;

Explanation:
PerformanceCounterType.SampleBase – A base counter that stores the number of sampling interrupts
taken and is used as a denominator in the sampling fraction. The sampling fraction is the number of samples
that were 1 (or true) for a sample interrupt. Check that this value is greater than zero before using it as the
denominator in a calculation of SampleFraction.
PerformanceCounterType.SampleFraction – A percentage counter that shows the average ratio of hits
to all operations during the last two sample intervals. Formula: ((N 1 – N 0) / (D 1 – D 0)) x 100, where the
numerator represents the number of successful operations during the last sample interval, and the denominator
represents the change in the number of all operations (of the type measured) completed during the sample
interval, using counters of type SampleBase. Counters of this type include Cache\\Pin Read Hits %.
http://msdn.microsoft.com/en-us/library/system.diagnostics.performancecountertype.aspx