The total capacity of a VSA cluster is the sum of the capacities of all VSA datastores. Depending on the RAID configuration of your VSA cluster, you use different algorithms to calculate VSA capacity.

The VSA datastore capacity is calculated after ESXi installation takes hard disk space for root, swap, and dump partitions and after VSA installation reserves 20GB or more for local virtual machine swap files. Because of this, calculations of the VSA cluster capacity are approximate.