High resolution timer in .NET

Question

I\'d like to do some basic profiling of my code, but found that the DateTime.Now in C# only have a resolution of about 16 ms. There must be better time keeping constructs th

Answer 1

For highest resolution performance counters you can use the underlying win32 performance counters.

Add the following P/Invoke sigs:

[System.Runtime.InteropServices.DllImport("Kernel32.dll")]
public static extern bool QueryPerformanceCounter(out long perfcount);

[System.Runtime.InteropServices.DllImport("Kernel32.dll")]
public static extern bool QueryPerformanceFrequency(out long freq);

And call them using:

#region Query Performance Counter
/// 

/// Gets the current 'Ticks' on the performance counter
/// 
/// Long indicating the number of ticks on the performance counter
public static long QueryPerformanceCounter()
{
    long perfcount;
    QueryPerformanceCounter(out perfcount);
    return perfcount;
}
#endregion

#region Query Performance Frequency
/// 

/// Gets the number of performance counter ticks that occur every second
/// 
/// The number of performance counter ticks that occur every second
public static long QueryPerformanceFrequency()
{
    long freq;
    QueryPerformanceFrequency(out freq);
    return freq;
}
#endregion

Dump it all into a simple class and you're ready to go. Example (assuming a class name of PerformanceCounters):

long startCount = PerformanceCounter.QueryPerformanceCounter();
// DoStuff();
long stopCount = PerformanceCounter.QueryPerformanceCounter();
long elapsedCount = stopCount - startCount;
double elapsedSeconds = (double)elapsedCount / PerformanceCounter.QueryPerformanceFrequency();
MessageBox.Show(String.Format("Took {0} Seconds", Math.Round(elapsedSeconds, 6).ToString()));