Installation guide

Glossary
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operating systems. Software virtualization is significantly slower
than hardware-assisted virtualization or para-virtualization.
Software virtualization, in the form of QEMU or BORCH, works in
Red Hat Enterprise Linux, it's just slow.
Red Hat Enterprise Linux supports hardware-assisted, full
virtualization with the KVM hypervisor.
Virtualized CPU A system has a number of virtual CPUs (VCPUs) relative to the
number of physical processor cores. The number of virtual CPUs is
finite and represents the total number of virtual CPUs that can be
assigned to guest virtual machines.
Xen Xen is not available as a hypervisor type for Red Hat Enterprise Linux
6 and newer. Xen is only supported for Red Hat Enterprise Linux 5
and newer.
Red Hat Enterprise Linux 5 supports the Xen hypervisor and the KVM
hypervisor (refer to Kernel-based Virtual Machine). Both hypervisors
have different architectures and development approaches. The Xen
hypervisor runs underneath a Red Hat Enterprise Linux operating
system which acts as a host managing system resources and
virtualization APIs.
Red Hat Enterprise Linux 6 is supported as a para-virtualized and
fully-virtualized guest of Red Hat Enterprise Linux 5.4 (and newer)
running the Xen hypervisor. Red Hat Enterprise Linux 6 is also
supported as a guest of the Red Hat Enterprise Linux 5.4 (and newer)
running the KVM hypervisor.