PercentIdleTime performnace counter delivers 0 for specific CPU

Hi All,

the Win32_PerfRawData_PerfOS_Processor object delivers sometimes 0
for the PercentIdleTime counter of a specific processor.

I have the problem with the following environment:

- W2K3 SP1 Enterprise Edition on a Itanium2 system with 2 CPUs
- local VC++ program on the system
(see the following coding derived from
http://msdn2.microsoft.com/en-us/library/aa390423.aspx )

Output of the program:

Connected to ROOT\CIMV2 WMI namespace
Name : 0
PercentIdleTime : 10388351700000
Name : 1
PercentIdleTime : 0
Name : _Total
PercentIdleTime : 5194175850000

The value of CPU 1 is 0 and the Total value is the half
of the CPU 0 value.

Then I tried the following VB script on the local system:

strComputer = "."
Set objWMIService = GetObject("winmgmts:\\" & strComputer &
"\root\cimv2")
Set colItems = objWMIService.ExecQuery _
("Select * From Win32_PerfRawData_PerfOS_Processor")

For Each objItem in colItems
Wscript.Echo "for CPU: " & objItem.Name & " " & "PercentIdleTime =
" & objItem.PercentIdleTime
Next

Output of the script:

for CPU: 0 PercentIdleTime = 10388253200000
for CPU: 1 PercentIdleTime = 10387550800000
for CPU: _Total PercentIdleTime = 10387902000000

This looks fine.
Wbemtest approves the values of the VB script.

Then I did a remote call from a Win XP system with a similar VC++
program
and saw the values of the VB script.

Whats wrong running the program on the local machine?
Any suggestions would be greatly appreciated!

Enno

----------------------------------------------------

#define _WIN32_DCOM
#include <iostream>
using namespace std;
#include <comdef.h>
#include <Wbemidl.h>
#include <conio.h>

# pragma comment(lib, "wbemuuid.lib")

int main(int argc, char **argv)
{
HRESULT hres;

// Step 1: --------------------------------------------------
// Initialize COM. ------------------------------------------

hres = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hres))
{
cout << "Failed to initialize COM library. Error code = 0x"
<< hex << hres << endl;
return 1; // Program has failed.
}

// Step 2: --------------------------------------------------
// Set general COM security levels --------------------------
// Note: If you are using Windows 2000, you need to specify -
// the default authentication credentials for a user by using
// a SOLE_AUTHENTICATION_LIST structure in the pAuthList ----
// parameter of CoInitializeSecurity ------------------------

hres = CoInitializeSecurity(
NULL,
-1, // COM authentication
NULL, // Authentication services
NULL, // Reserved
RPC_C_AUTHN_LEVEL_DEFAULT, // Default authentication
RPC_C_IMP_LEVEL_IMPERSONATE, // Default Impersonation
NULL, // Authentication info
EOAC_NONE, // Additional capabilities
NULL // Reserved
);


if (FAILED(hres))
{
cout << "Failed to initialize security. Error code = 0x"
<< hex << hres << endl;
CoUninitialize();
return 1; // Program has failed.
}

// Step 3: ---------------------------------------------------
// Obtain the initial locator to WMI -------------------------

IWbemLocator *pLoc = NULL;

hres = CoCreateInstance(
CLSID_WbemLocator,
0,
CLSCTX_INPROC_SERVER,
IID_IWbemLocator, (LPVOID *) &pLoc);

if (FAILED(hres))
{
cout << "Failed to create IWbemLocator object."
<< " Err code = 0x"
<< hex << hres << endl;
CoUninitialize();
return 1; // Program has failed.
}

// Step 4: -----------------------------------------------------
// Connect to WMI through the IWbemLocator::ConnectServer method

IWbemServices *pSvc = NULL;

// Connect to the root\cimv2 namespace with
// the current user and obtain pointer pSvc
// to make IWbemServices calls.
hres = pLoc->ConnectServer(
_bstr_t(L"ROOT\\CIMV2"), // Object path of WMI namespace
NULL, // User name. NULL = current user
NULL, // User password. NULL = current
0, // Locale. NULL indicates current
NULL, // Security flags.
0, // Authority (e.g. Kerberos)
0, // Context object
&pSvc // pointer to IWbemServices proxy
);

if (FAILED(hres))
{
cout << "Could not connect. Error code = 0x"
<< hex << hres << endl;
pLoc->Release();
CoUninitialize();
return 1; // Program has failed.
}

cout << "Connected to ROOT\\CIMV2 WMI namespace" << endl;


// Step 5: --------------------------------------------------
// Set security levels on the proxy -------------------------

hres = CoSetProxyBlanket(
pSvc, // Indicates
the proxy to set
RPC_C_AUTHN_WINNT, // RPC_C_AUTHN_xxx
RPC_C_AUTHZ_NONE, // RPC_C_AUTHZ_xxx
NULL, // Server
principal name
RPC_C_AUTHN_LEVEL_CALL, // RPC_C_AUTHN_LEVEL_xxx
RPC_C_IMP_LEVEL_IMPERSONATE, // RPC_C_IMP_LEVEL_xxx
NULL, // client
identity
EOAC_NONE // proxy capabilities
);

if (FAILED(hres))
{
cout << "Could not set proxy blanket. Error code = 0x"
<< hex << hres << endl;
pSvc->Release();
pLoc->Release();
CoUninitialize();
return 1; // Program has failed.
}

// Step 6: --------------------------------------------------
// Use the IWbemServices pointer to make requests of WMI ----

// For example, get the name of the operating system
IEnumWbemClassObject* pEnumerator = NULL;
hres = pSvc->ExecQuery(
bstr_t("WQL"),
bstr_t("SELECT * FROM Win32_PerfRawData_PerfOS_Processor"),
WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
NULL,
&pEnumerator);

if (FAILED(hres))
{
cout << "Query for operating system name failed."
<< " Error code = 0x"
<< hex << hres << endl;
pSvc->Release();
pLoc->Release();
CoUninitialize();
return 1; // Program has failed.
}

// Step 7: -------------------------------------------------
// Get the data from the query in step 6 -------------------

IWbemClassObject *pclsObj;
ULONG uReturn = 0;

while (pEnumerator)
{
HRESULT hr = pEnumerator->Next(WBEM_INFINITE, 1,
&pclsObj, &uReturn);

if(0 == uReturn)
{
break;
}

VARIANT vtProp;

// Get the value of the Name property
hr = pclsObj->Get(L"Name", 0, &vtProp, 0, 0);
wcout << " Name : " << vtProp.bstrVal << endl;
VariantClear(&vtProp);

hr = pclsObj->Get(L"PercentIdleTime", 0, &vtProp, 0, 0);
wcout << " PercentIdleTime : " << vtProp.bstrVal << endl;
VariantClear(&vtProp);

}

// Cleanup
// ========

pSvc->Release();
pLoc->Release();
pEnumerator->Release();
pclsObj->Release();
CoUninitialize();

char c = _getch();

return 0; // Program successfully completed.

}

.

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