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When adding additional virtual hard drives (VMDKs) to a virtual machine, consider the following two virtual SCSI controller changes.
Virtual machines can be configured with extra SCSI controllers. Each SCSI controller not only enables a greater number of VMDKs to be added to the virtual machine, it also adds a separate disk queue. These separate disk queues can prevent contention for I/O between VMDKs. Adding virtual SCSI controllers requires the same process as adding any virtual hardware to a virtual machine, through the Edit settings menu.
There are several virtual SCSI controllers. By, default any extra virtual SCSI controllers are of the default type for that guest operating system. For example, the default virtual SCSI controller with Windows Server 2022 is LSI Logic SAS. However, the VMware Paravirtual (PVSCSI) virtual SCSI controller has a lower host CPU cost per I/O, freeing up those CPU cycles for more valuable uses. Check the VMware Guest OS Compatibility Guide to ensure that the Paravirtual controller is compatible with the virtual machine operating system.