Design requirements, virtual machine disk size, IOPS, and recovery are all factors that can determine the number of virtual machines to store on a single datastore. The size of the datastore is calculated based on the number of virtual machines per datastore and the size of the virtual machines:

1. Determine the number of virtual machines per datastore based on the capacity, performance, and recovery requirements
2. Understand the impact the SCSI reservations may have on datastore sizing
3. Understand how recovery time impacts datastore sizing