With Linux 3.0 the Xen Hypervisor now can run natively with Dom0

“The Xen hypervisor now can run natively with Dom0 (Domain 0) privileges. This gives it, like Linux’s Kernel-based Virtual Machine (KVM), the ability to work at the lowest possible level of the Linux kernel. In practical terms this means Xen virtual machines should run faster.”

wow, virtualization i love it…

source: here

Monolithic Kernel vs Microkernel

Monolithic Kernel
A monolithic kernel is a kernel architecture where the entire kernel is run in kernel space in supervisor mode. In common with other architectures (microkernel, hybrid kernels), the kernel defines a high-level virtual interface over computer hardware, with a set of primitives or system calls to implement operating system services such as process management, concurrency, and memory management in one or more modules.

A microkernel is a minimal computer operating system kernel which, in its purest form, provides no operating-system services at all, only the mechanisms needed to implement such services, such as low-level address space management, thread management, and inter-process communication (IPC)