c# - 使用性能计数器的 % Processor Time 值不一致

Question

我有以下类监视系统以查看我的程序使用的总 cpu 和系统的总 cpu 使用率。问题是有时，当我调用 GetHealthInformation 方法时，我的程序 % CPU 大于系统的 % CPU。这是我的代码：

    public class MonitoringManager : AbstractComponent, IMonitoringManager, IStaticComponent {
    private static PerformanceCounter totalCpuCounter = new PerformanceCounter("Processor", "% Processor Time", "_Total"); 
    private static PerformanceCounter cpuCounterMyProgram = new PerformanceCounter("Process", "% Processor Time", Process.GetCurrentProcess().ProcessName);
    private static DateTime lastUpdate = DateTime.UtcNow;

    public void Load() {
        cpuCounterMyProgram.NextValue();
        totalCpuCounter.NextValue();
    }

    public  HealthInfo GetHealthInformation(){
        var now = DateTime.UtcNow;
        if((now - lastUpdate).TotalMilliseconds <1000){
            Thread.Sleep(1000);
        }
        lastUpdate = now;
        return new HealthInfo(totalCpuCounter.NextValue(), cpuCounterMyProgram.NextValue() / Environment.ProcessorCount);

    }

}


    public class HealthInfo{

    [DataMember]
    public float CpuTotal { get; set; }

    [DataMember]
    public float CpuMyProgram { get; set; }


    public HealthInfo(float cpuTotal, float cpuMyProgram){
        CpuTotal = cpuTotal;
        CpuMyProgram = cpuMyProgram;           
    }

    #endregion IConstructors
}

}

怎么了？为什么有时系统的总 % CPU 是 0% 而我的程序是 2% ??