AMD Viirtualization Technology

[mudha]

hello,

do i need to enable to AMD -virtualization technoly in BIOS to have vmotion or to have 64 bit vm's as earlier it was like all AMD procs are capble to install 64 bit vm's without enaleing it

DOes this statement is true right now??

or we need to enale VT for AMD platform also

Thanks in advance.

[admin]

AMD-V is optional for running 64-bit VMs on AMD hardware, but it can provide improved performance for some workloads. It has no effect on VMotion.

VT-x is required for running 64-bit VMs on Intel hardware.

[mudha]

thnaks can you let me know exactly changes made to the processor core when i enale AMD-v and why VMware is dependant on Intel VT to have 64 bit vm's running not the case with AMD

Thank you

[admin · Accepted solution]

Enabling AMD-V permits the use of the hardware virtualization features of the CPU. Specifically, it enables the instructions CLGI, STGI, VMLOAD, VMSAVE, and VMRUN. If these instructions are not used, processor behavior is the same.

VT-x is required on Intel chips because Intel does not implement segment limit checks in 64-bit mode. All AMD64 chips except for the very earliest 64-bit Opterons do. VMware's software virtualization technology relies on segment limit checks to isolate the guest from the hypervisor. See KB 1901.

[mudha]

Thanks Mattson