INFO: Percent Total Performance Counter Changes on Windows (259390)

SUMMARY

Some counters have been moved in Microsoft Windows 2000 and Microsoft Windows XP. Applications that use the PdhAddCounter function to collect data for these counters may fail with PDH_CSTATUS_NO_COUNTER. Applications that use the RegQueryValueEx function with HKEY_PERFORMANCE_DATA may not find these counters in the performance data. This article explains how to find the counters on a computer that is running Windows 2000 and Windows XP.

MORE INFORMATION

On a computer that is running Microsoft Windows NT 4.0, the following counters are available under System Performance Object:

System\% Total DPC Time
System\% Total Interrupt Time
System\% Total Privileged Time
System\% Total Processor Time
System\% Total User Time

However, in Windows 2000 and Windows XP, these counters are moved to Processor Performance Object. These counters have a processor instance that is associated with them (named starting with 0, 1, and so on), and _Total instance name for the Total.

The following are the corresponding counters in Processor Performance Object:

Processor(_Total)\% DPC Time
Processor(_Total)\% Interrupt Time
Processor(_Total)\% Privileged Time
Processor(_Total)\% Processor Time
Processor(_Total)\% User Time

The application must retrieve the counter data information that is associated with the _Total instance name for getting the same performance data information, such as percent Total counters in System Performance Object on a computer that is running Windows NT 4.0.

REFERENCES

For detailed information about retrieving these counter values, refer to Performance Monitoring topic in the Microsoft Platform SDK or the Microsoft Developers Network (MSDN) documentation under Base Services.