How to use AverageTimer32 and AverageBase performance counters with System.Diagnostics.Stopwatch?

Question

When I execute the following program and look at the performance counter the results don\'t make sense to me. The average value is zero and the min/max values are ~0.4 when I w

Answer 1

This is an old thread, but I thought I'd chime in. I was told by someone from Microsoft that I shouldn't use TimeSpan, StopWatch, or DateTime when working with Performance Counters. Instead, he recommended adding the following native method to my project:

internal static class NativeMethods
{
    [DllImport("Kernel32.dll")]
    public static extern void QueryPerformanceCounter(ref long ticks); 
}

When incrementing a counter, he recommended doing so like this:

public void Foo()
{
    var beginTicks = 0L;

    var endTicks = 0L;

    NativeMethods.QueryPerformanceCounter(ref beginTicks);

    // Do stuff

    NativeMethods.QueryPerformanceCounter(ref endTicks);

    this.Counter.IncrementBy(endTicks - beginTicks);
    this.BaseCounter.Increment();
}

Answer 2

The System.Diagnostics API contains a pretty subtle source of great confusion: System.Diagnostics 'ticks' are not the same as DateTime or TimeSpan 'ticks'!

If you use StopWatch.ElapsedTicks instead of StopWatch.Elapsed.Ticks, it should work.

The documentation contains more information about this.

Answer 3

Mark Seemann explained the confusing source of the problem but I would like to provide a little bit of additional information.

If you want to set your AverageTimer32 performance counter from a TimeSpan and not a Stopwatch you can perform the following conversion:

var performanceCounterTicks = timeSpan.Ticks*Stopwatch.Frequency/TimeSpan.TicksPerSecond;
averageTimerCounter.IncrementBy(performanceCounterTicks);
averageTimerCounterBase.Increment();