如何在System.Diagnostics.Stopwatch中使用AverageTimer32和AverageBase性能計數器？

Question

當我執行以下程序並查看性能計數器時，結果對我來說沒有意義。當我期望〜0.1或〜100時，平均值爲零，最小/最大值爲〜0.4。

我的問題是什麼？

代碼

class Program 
{ 
    const string CategoryName = "____Test Category"; 
    const string CounterName = "Average Operation Time"; 
    const string BaseCounterName = "Average Operation Time Base"; 

    static void Main(string[] args) 
    { 
     if (PerformanceCounterCategory.Exists(CategoryName)) 
      PerformanceCounterCategory.Delete(CategoryName); 

     var counterDataCollection = new CounterCreationDataCollection(); 

     var avgOpTimeCounter = new CounterCreationData() 
     { 
      CounterName = CounterName, 
      CounterHelp = "Average Operation Time Help", 
      CounterType = PerformanceCounterType.AverageTimer32 
     }; 
     counterDataCollection.Add(avgOpTimeCounter); 

     var avgOpTimeBaseCounter = new CounterCreationData() 
     { 
      CounterName = BaseCounterName, 
      CounterHelp = "Average Operation Time Base Help", 
      CounterType = PerformanceCounterType.AverageBase 
     }; 
     counterDataCollection.Add(avgOpTimeBaseCounter); 

     PerformanceCounterCategory.Create(CategoryName, "Test Perf Counters", PerformanceCounterCategoryType.SingleInstance, counterDataCollection); 

     var counter = new PerformanceCounter(CategoryName, CounterName, false); 
     var baseCounter = new PerformanceCounter(CategoryName, BaseCounterName, false); 

     for (int i = 0; i < 500; i++) 
     { 
      var sw = Stopwatch.StartNew(); 
      Thread.Sleep(100); 
      sw.Stop(); 

      Console.WriteLine(string.Format("t({0}) ms({1})", sw.Elapsed.Ticks, sw.Elapsed.TotalMilliseconds)); 
      counter.IncrementBy(sw.Elapsed.Ticks); 
      baseCounter.Increment(); 
     } 

     Console.Read(); 
    } 
} 

性能計數器截圖 Performance Counter Screenshot http://friendfeed-media.com/50028bb6a0016931a3af5122774b56f93741bb5c

Answer 1

的System.Diagnostics程序API包含了極大的混亂的一個非常微妙來源：System.Diagnostics程序 '滴答' 是不一樣的DateTime或TimeSpan'勾號'！

如果您使用StopWatch.ElapsedTicks而不是StopWatch.Elapsed.Ticks，它應該工作。

該documentation包含更多信息。

Answer 2

Mark Seemann解釋了這個問題的原因，但我想提供一些額外的信息。

如果你想從TimeSpan，而不是一個Stopwatch可以執行下面的轉換設置您AverageTimer32性能計數器：

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

Answer 3

這是一個古老的線程，但我想我會附和我微軟的一位人士告訴我，在使用性能計數器時，我不應該使用TimeSpan,StopWatch或DateTime。相反，他建議增加以下本地方法到我的項目：

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

當遞增計數器，他建議這樣做是這樣的：

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(); 
}