Xen is a virtual machine monitor, or an operating system contained inside another, for x86 that supports execution of multiple guest operating systems with unprecedented levels of performance and resource isolation. It requires a part of the kernel to be modified. Works on Linux 2.4 and 2.6, FreeBSD, NetBSD and Plan 9. The guest OS requires no modification of source code. A port of Windows XP was developed for an earlier version of Xen, but is not available for release due to licence restrictions.
According to the benchmarks on the site, it is much faster than both VMware and UML with only a 10% overhead. A disadvantage of Xen is being part of the host OS kernel needs to be recoded or patched. Also, VMware is a commercial and closed source app and UML is made to only run Linux inside of Linux solely.
- Emulator – Various emulators, virtual machines and API implementations.
- Linux-mag.com: Now and Xen – “Xen, a new, high-performance x86 virtualization system, saves money, boosts usage”
- Slashdot: IBM Pledges To Make Xen More Secure
TakeDown.NET -> “Xen”