This article answers some questions referred to Processor Queue Length metric that can be retrieved by the ntperf probe.
Any supported ntperf probe version.
Q: We would like to understand how ntperf captures the Processor Queue Length data from the windows server and trigger alerts in UIM ?
A: The Performance Collector (ntperf) probe can monitor the windows performance objects and their respective counters and instances on a Windows system. The probe is configured to send alarms on unexpected values and generate quality of service (QoS) messages.
So basically, the ntperf probe gets the Windows Performance Monitor data via the Windows API's (exactly like CDM probe).
Related to "Processor Queue Length" counter, It is located under Object: System -> Processor Queue Length.
There really isn't any difference between CDM and ntperf probes, related to this subject. We suggest avoiding using ntperf to get this metric, unless you are gathering other metrics since it would be another probe to manage. Ntperf is a bit more complicated, due to how Microsoft implemented it so you have to watch out for the "Scale". So is it 1 to 1, or 1 to .01, etc. With CDM probe, you don't have to worry about that.
Q: Can I get documentation on this parameter?
A: This parameter is not documented in ntperf probe documentation. However, as mentioned above, ntperf works in the same way as CDM probe to get this info, so for this parameter, you can refer to CDM probe documentation: