Take the 2-minute tour ×
Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

enter image description here

The server sits on RAIDed SSD drives too.

Is there a reason why the host machine seems to get more CPU over a VM in Hyper-V?

The guest machine is at 100% CPU while the HOST is only at 20%. Anywa idea why?

share|improve this question

2 Answers 2

up vote 2 down vote accepted

The "Host" in Hyper-V is actually a special Virtual Machine itself. The VM's are not "running on it", though the Hyper-V hypervisor use's the Host for file and network access as well as a few other things. What the Host reports it's doing is not an accurate reflection of what the hardware is actually doing. I've actually not found an accurate way of profiling CPU and Memory IO in Hyper-V.

As TomTom noted, the "Host" does receive preference over VMs in CPU scheduling.

Similar questions:

share|improve this answer

The Host has piriority because it is supposed to ONLY run Hyper-V (and system control packages like SCOM) and if it would not get what it needs, all VM's would be starved.

share|improve this answer
    
So even though the HOST has lots of CPU power it still will limit the VM? –  Frank Thornton Nov 30 '13 at 15:16
    
Actually no because if you use Hyper-V as you should then there is nothing the host is using it for. If you run CPU intensive tasks on the host - then yes, it will use what it can and the rest goes to the VM's. Host has priority. –  TomTom Dec 2 '13 at 3:36

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.