Extended Page Table
Encyclopedia
Extended Page Tables is an Intel second generation x86 virtualization
technology for the memory management unit
(MMU). When this feature is active, the ordinary IA-32 page tables (referenced by control register
CR3) translate from linear addresses to guest-physical addresses. A separate set of page tables (the EPT tables) translate from guest-physical addresses to the host-physical addresses that are used to access memory. As a result, guest software can be allowed to modify its own IA-32 page tables and directly handle page faults. This allows a virtual machine monitor (VMM) to avoid the VM exits associated with page-table virtualization, which are a major source of virtualization overhead without EPT.
s.
It is not available in Core 2-based and earlier Intel CPUs.
X86 virtualization
In computing, x86 virtualization is the facility that allows multiple operating systems to simultaneously share x86 processor resources in a safe and efficient manner, a facility generically known as hardware virtualization...
technology for the memory management unit
Memory management unit
A memory management unit , sometimes called paged memory management unit , is a computer hardware component responsible for handling accesses to memory requested by the CPU...
(MMU). When this feature is active, the ordinary IA-32 page tables (referenced by control register
Control register
A control register is a processor register which changes or controls the general behavior of a CPU or other digital device. Common tasks performed by control registers include interrupt control, switching the addressing mode, paging control, and coprocessor control.-CR0:The CR0 register is 32 bits...
CR3) translate from linear addresses to guest-physical addresses. A separate set of page tables (the EPT tables) translate from guest-physical addresses to the host-physical addresses that are used to access memory. As a result, guest software can be allowed to modify its own IA-32 page tables and directly handle page faults. This allows a virtual machine monitor (VMM) to avoid the VM exits associated with page-table virtualization, which are a major source of virtualization overhead without EPT.
Hardware support
Intel states that the feature is available in all their Nehalem-based CPUs with virtualization support; namely in Core i7, Core i5, Core i3, Pentium G6950 and appropriate XeonXeon
The Xeon is a brand of multiprocessing- or multi-socket-capable x86 microprocessors from Intel Corporation targeted at the non-consumer server, workstation and embedded system markets.-Overview:...
s.
It is not available in Core 2-based and earlier Intel CPUs.