Storage-sizing formulas can help you estimate how much disk space is required on the datastores that you select for OS disks and replicas.

## Storage Sizing Formulas

Storage Sizing Formulas for Clone Disks on Selected Datastores shows the formulas that calculate the estimated sizes of the disks when you create a pool and as the clones grow over time. These formulas include the space for replica disks that are stored with the clones on the datastore.

If you edit an existing pool or store replicas on a separate datastore, VMware Horizon 8 uses a different sizing formula. See Sizing Formulas for Creating Clones When You Edit a Pool or Store Replicas on a Separate Datastore.

Table 1. Storage Sizing Formulas for Clone Disks on Selected Datastores
Data Type Selected Free Space (GB) Min Recommended (GB) 50% Utilization (GB) Max Recommended (GB)
OS disks Free space on the selected datastores Number of VMs * (2 * memory of VM) + (2 * replica disk) Number of VMs * (50% of replica disk + memory of VM) + (2 * replica disk) Number of VMs * (100% of replica disk + memory of VM) + (2 * replica disk)

## Example of a Storage Sizing Estimate

In this example, the golden image is configured with 1GB of memory. The golden image's disk size is 10GB. A pool is created with 10 machines.

The OS disks are configured on a datastore that currently has 184.23GB of available space.

Example of a Sizing Estimate for Clone Disks Deployed on Selected Datastores shows how the sizing formulas calculate estimated storage requirements for the sample desktop pool.

Table 2. Example of a Sizing Estimate for Clone Disks Deployed on Selected Datastores
Data Type Selected Free Space (GB) Min Recommended (GB) 50% Utilization (GB) Max Recommended (GB)
OS disks 184.23 10 * (2*1GB) + (2*10GB) =

40.00

10 * (50% of 10GB + 1GB) + (2*10GB) =

80.00

10 * (100% of 10GB + 1GB) + (2*10GB) =

130.00