When deploying a Dual-SP (Storage Processor) Dell Unity VSA (Virtual Storage Appliance), the recommended disk format is Thick Provision Eager Zeroed. This format pre-allocates storage capacity and zeros out all blocks at the time of creation, which ensures better performance and reliability compared to thin provisioning or lazy zeroed formats. This is especially important for high-performance storage environments.
Reference:Dell Unity VSA Deployment Guide

Reference: https://www.delltechnologies.com/asset/en-us/products/storage/industry- market/h18157-dell-emc-powerstore-clustering-high-availability.pdf

When the administrator adds 4x 3.84 TB SSD drives to a RAID 5 dynamic pool in a Dell Unity XT 380F system, the full capacity of the new drives will be available. Dell Unity XT systems support mixing different drive sizes within a dynamic pool, allowing administrators to expand the storage capacity seamlessly.