Hypervisor API returns CPUs as VCPUs

[Sam Morrison]

The stats returns in the hypervisor API are incorrect.

Eg it returns vcpu when they are actually cpus. (or cores to be precise, I think....)

Eg you can have: vcpus = 64 and vcpus_used = 67 (when over allocating)
vcpus should take into account the over allocation ratio.

This is also the case for memory.

Here is an example:

 u'current_workload': 0,
 u'disk_available_least': 2476,
 u'free_disk_gb': 3087,
 u'free_ram_mb': -17108,
 u'hypervisor_type': u'QEMU',
 u'hypervisor_version': 1000000,
 u'local_gb': 5357,
 u'local_gb_used': 2270,
 u'memory_mb': 257836,
 u'memory_mb_used': 274944,
 u'running_vms': 26,
 u'vcpus': 64,
 u'vcpus_used': 67

[Guangya Liu (Jay Lau) (jay-lau-513)]

Its an interesting problem, we did encounter this many times. I think it is a good time to do some enhancement in Icehouse.

Not only cpu and memory, but disk also have such issue.

A possbile solution was that add some new fields in DB to record the cpu/memory/disk that have been multipled by allocation ratio, but not update vcpus/memory_mb/free_disk_gb directly.

I think that it might be better to log a blueprint to trace this, as this is more like to be a feature