C# CPU사용율 알아내기

private ManagementPath cpuPath = null; private ManagementObject cpuObject = null; private ManagementScope scope = null; private ulong oldCpuValue, oldNanoValue; public void SetWMIObject() { this.cpuPath = new ManagementPath(); this.cpuPath.RelativePath = "Win32_PerfRawData_PerfOS_Processor.Name='_Total'"; this.cpuObject = new ManagementObject(this.scope, cpuPath, null); } public decimal ObtainCpuPerformance() { decimal percentProcessorTime = 0; cpuObject.Get(); ulong u_CurrentCPU = (ulong)cpuObject.Properties["PercentProcessorTime"].Value; ulong u_CurrentNano = (ulong)cpuObject.Properties["TimeStamp_Sys100NS"].Value; decimal d_CurrentCPU = Convert.ToDecimal(u_CurrentCPU); decimal d_CurrentNano = Convert.ToDecimal(u_CurrentNano); decimal d_OldCPU = Convert.ToDecimal(oldCpuValue); decimal d_OldNano = Convert.ToDecimal(oldNanoValue); percentProcessorTime = (1 - ((d_CurrentCPU - d_OldCPU) / (d_CurrentNano - d_OldNano))) * 100m; oldCpuValue = u_CurrentCPU; oldNanoValue = u_CurrentNano; return percentProcessorTime; }