When we talk about storage performance, we are mainly talking about the amount of read and write I/O per second that the storage can serve. There are many factors that affect the overall I/O performance of the store, such as the physical disks or SSDs that are used by the storage, the maturity of the storage controller, the physical media, and the protocols used, or the IO size. Usually, the most important components are as follows:

• The Redundant Array of Independent Disks (RAID) level of the logical volume presented to the ESXi servers
• The device type that is used to form a logical volume