The Performance Tuning Guidelines for Windows Server 2012 document is available and I’m reviewing and commenting on notable text in it.
You cannot get true performance monitoring of a VM by running Performance Monitor or Task Manager from within a guest OS. In fact, you can’t even get true accurate monitoring on the management OS using the normal metrics. You should use either PerfMon or Longman.exe from the Management OS to monitor the Hyper-V counter objects.
If you want to monitor the CPU usage of the physical host or VM then you use the Hyper-V Hypervisor Logical Processor performance counters:
- Hyper-V Hypervisor Logical Processor (*) % Total Run Time: The counter represents the total non-idle time of the logical processor(s).
- Hyper-V Hypervisor Logical Processor (*) % Guest Run Time: The counter represents the time spent running cycles within a guest or within the host.
- Hyper-V Hypervisor Logical Processor (*) % Hypervisor Run Time: The counter represents the time spent running within the hypervisor.
- Hyper-V Hypervisor Root Virtual Processor (*) *: The counters measure the CPU usage of the management OS.
- Hyper-V Hypervisor Virtual Processor (*) *: The counters measure the CPU usage of guest partitions.