Virtual Fibre Channel HBAs can be configured to allow direct access for virtual machines to Fibre Channel and Fibre Channel over Ethernet (FCoE) LUNs. Introduced in Windows Server 2012 R2, this controller is reported as SAS to support shared VHDX. In fact with Generation 2 VMs, it is the only type of controller possible. SCSI path is not emulated which makes it the preferred controller for any disk other than the operating system disk. For optimal performance, we recommend that you attach multiple disks to a single virtual SCSI controller and create additional controllers only as they are required to scale the number of disks connected to the virtual machine. SCSI controllers expose SCSI disks to the virtual machine, and each virtual SCSI controller can support up to 64 devices. We recommend that IDE disks be used only for the operating system disks because they have performance limitations due to the maximum I/O size that can be issued to these devices. Disk I/O that is performed by using the IDE filter driver that is provided with the Virtual Machine Integration Services is significantly better than the disk I/O performance that is provided with the emulated IDE controller. The IDE controller is emulated, and it is the only controller that is available for guest VMs running older version of Windows without the Virtual Machine Integration Services. IDE controllers expose IDE disks to the virtual machine. Hyper-V offers three types of virtual controllers: IDE, SCSI, and Virtual host bus adapters (HBAs). Following are explanations about how optimizations are possible at each of these stages. The storage I/O path extends from the guest storage stack, through the host virtualization layer, to the host storage stack, and then to the physical disk. This section describes the different options and considerations for tuning storage I/O performance in a virtual machine.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |