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Before discussing the type of virtual disks to use, it is worth mentioning the disk controllers and whether Dell prefers one type of controller over another.
There are three types of controllers as of the current vSphere 7.0 release: SCSI, NVMe, and SATA. When a new VM is created, the GuestOS selection drives the controller that VMware selects by default. For instance, if macOS is selected, VMware assigns a SATA controller. If Windows or Linux is selected, as SCSI controller is assigned. In addition, VMware also assigns a SCSI controller “type.” These types are:
For most Windows GuestOS VMware assigns LSI Logic SAS, and for Linux, PVSCSI. Though there are some differences, these two types are similar and can be used interchangeably.
For most situations, Dell Technologies recommends keeping the VMware default assignment of the controller and type. For environments with intensive I/O, the PVSCSI generally provides better performance and use fewer CPU cycles. PVSCSI is recommended under those conditions; but there is no requirement to change the controller type.
The NVMe controller is designed to improve performance while reducing CPU overhead when accessing high-performing NVMe media. Hardware version 13 is required along with a supported GuestOS. This requirement usually entails installing a driver if the operating system does not have one natively. The NVMe controller is assigned by default when using a newer version of Windows GuestOS (for example, 2016). There are some limitations with the NVMe controller, and it does not work with all applications. Thoroughly reviewing the requirements is important. VMware indicates the NVMe controller may provide better performance for NVMe. However, VMware also clearly states that when using the HPP plug-in for pathing, using PVSCSI is a best practice. Ultimately, for customers using NVMeoF on the PowerMax, either controller type is acceptable. Testing is always recommended.
Note: Changing the controller type or controller itself on an existing VM may require that certain steps are completed. See VMware article 341383 for more detail.