Org VDC Monitoring in vCloud Director

I had a question from customer how to interpret the numbers reported in Organization VDC monitoring tab in vCloud Director. It is in Administration > Virtual Datacenter menu. If you are using vCloud Hybrid Service it is also displayed in the dashboard on homepage for each Virtual Datacenter (in the lower part of the screen).

OrgVDC Monitoring

vCHS Dashboard

It is not very intuitive and we have a KB article 203003 explaining that the displayed usage numbers (blue bars) do not actual correspond to real time resource usage but instead represent how many resources have been allocated by deployed VMs in the Org VDC. These values are updated every 5 minutes.

The next question would be why is CPU usage always 0 GHz in the pictures above?

I already wrote couple articles (here and here) about the new elastic Allocation Pool Org VDC in vCloud Director 5.1.x. Go back to read them to actually understand the reasoning behind the following formulas.

Elastic Allocation Pool Org VDC

CPU Used = Org VDC vCPU speed (in GHz) x # of vCPUs of deployed VMs in Org VDC
CPU Allocated = Org VDC CPU allocation (in GHz)

RAM Used = Total memory of VMs deployed in Org VDC (in GB)
RAM Allocated = Org VDC memory allocation (in GB)

If 1 VM with 1 vCPU of nominal value 1 GHz is deployed, it might use somewhere between 0 GHz up to 3 GHz (max physical core speed) but the CPU Used value in the graph will always be 1 GHz. Sounds confusing? Remember that the vCPU speed value is not a VM limit in Elastic Allocation Pool Org VDCs contrary to Pay As You Go Org VDCs.

Non-elastic Allocation Pool Org VDC

CPU Used = Always 0 as all VMs in Org VDC share its CPU allocation
CPU Allocated = Org VDC CPU allocation (in GHz)

RAM Used = Total memory of VMs deployed in Org VDC (in GB)
RAM Allocated = Org VDC memory allocation (in GB)

The storage numbers are always calculated same way for all Org VDC types:

Storage Used = Total allocated disk space of VMs deployed in Org VDC + Total memory of VMs deployed in Org VDC (to account for VM swap usage) + Maximum possible existing snapshot size

Storage allocated = Org VDC storage allocation

So if I have 1 VM with 1 GB RAM and 10 GB disk and create a snapshot (including memory), the storage usage will be: 10 GB (disk) + 1  GB (VM swap) + 10 GB (maximum disk snapshot size) + 1 GB (memory snapshot size) = 22 GB.

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Yes, vCHS is using non-elastic Allocation Pool Org VDCs

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