Blame AMD. They ruined PV performance on x84_64 when they removed two of the protection rings.
Hardware extensions still move the performance needle towards Xen (PV)HVM/PVH and KVM, but the extra context switches required due to the inferior (for paravirtualization) architecture are a major performance hit.
(PV, of course, performs IO better when there is not SRIOV access to the IO devices)
Hardware extensions still move the performance needle towards Xen (PV)HVM/PVH and KVM, but the extra context switches required due to the inferior (for paravirtualization) architecture are a major performance hit.
(PV, of course, performs IO better when there is not SRIOV access to the IO devices)