VMWare RAM and Storage Overhead Allocation
Why does Cloud Director report more RAM and Storage for my VDC than the amount I ordered and is shown in MyAccount?
Virtualisation incurs RAM and storage overheads for VMs. RAM overhead covers virtualisation components. Storage overhead includes files beyond VM disks and space for RAM snapshots written to disk.
When Zettagrid provisions VDCs, we add extra RAM and storage beyond the ordered (and billed) amounts to cover these overheads, ensuring customers can use their full ordered capacity. Customers should not allocate RAM or storage beyond their ordered amounts, as errors may occur if space for virtualisation overhead is insufficient.