2. RELATEDWORK
Commercial virtualization solutions for ARM platforms are provided
by Open Kernel Labs [OKL11], VMware [VMwa10] and Red Bend
Software [RedB10], these all use para-virtualization. Green Hills Software’s
Integrity product [Gree10] uses the TrustZone features of the
ARM architecture to run a native guest binary, but architecture limitations
restrict this to a single guest.
A port of Xen to ARM was performed by Samsung [HSH+08], but
performance is poor: a Linux guest runs at about half of native speed. In
contrast, the OKL4 microvisor from OK Labs, which is the only commercial
product for which performance data is available, exhibits overheads
which are about an order of magnitude lower [HL10]. NOVA
[SK10] is a hypervisor for x86 which, like the OKL4 microvisor and
our current design, uses a microkernel architecture aimed at minimising
the trusted computing base TCB of virtual machines (VMs).
Fisher-Ogden presented a thorough analysis of virtualization extensions
for x86 from Intel and AMD [FO06]. Adams and Agesen [AA06]
found that binary translation outperformed pure virtualization, but this
evaluation was completed before the hardware extensions included
MMU virtualization. A later evaluation [Bha09] found MMUvirtualization
significantly reduced overheads, especially when using large pages.
The ARM virtualization extensions already includeMMUvirtualization