I got question from a customer what is the meaning of the various datastore metrics in vCloud Director: used, provisioned and requested storage. These can be viewed at the Datastores & Datastores Cluster screen in the Manager & Monitor tab.
There are even more metrics when we open properties of a single datastore or a datastore cluster.
So let us go through them:
Total Capacity: Total size of the datastore or datastore cluster as reported by vCenter Server
Used Capacity: Actual used capacity of the datastore or the datastore cluster as reported by vCenter Server.
Available Capacity: Difference between the values above (Available Capacity = Total Capacity – Used Capacity)
I am including screenshot from vCenter Server of the same datastore:
Provisioned Capacity: Total storage provisioned of virtual machines residing on the datastore. This number might be much bigger than the actual datastore capacity if thin provisioning is used. Again, this number is reported by vCenter Server (can be seen in the Datastore and Datastore Clusters view on the Summary tab). I am again including relevant vCenter Server screenshot.
Requested Storage: This is the only metric coming directly from vCloud Director. It adds up storage for all vCloud Director provisioned virtual machines, catalog templates and media and vCNS (vShield) Edges. It uses allocated storage and also includes (even potential) memory swap for virtual machines (not for catalog VMs). It does not include storage occupied by shadow VMs or intermediate disks in a linked clone tree.