Tony Yarusso wrote: > The handful of things I can add to that: > > For home users, a major consideration in virtualization systems is > whether they require hardware support. Xen, KVM, and I would guess > ESX all require that your CPU have virtualization "extensions" / > "flags". In modern CPUs, almost all AMD ones have this (even in the > budget lines), but Intel restricts it a bit more to their higher-end > products. The older the CPU, the higher end it had to be to have > them, as the entry of this technology into the consumer market instead > of pure datacenter rigs is relatively recent. Due to this, my > personal experience so far is only with VirtualBox at home, as I don't > have that support and so needed this kind of product. (I also used > VMware Fusion briefly at work.) > > While I haven't had a chance to use them yet, I can point out some key > things about KVM and Xen. Both are bare-metal type hypervisors, like > ESX. Given that Xen runs on a standard OS for the host, I wouldn't call it a bare-metal hypervisor. One can make it essentially that by not running anything else in the host, but you still can run a full OS in the host. > In addition to the usual x86 and x86_64, both also work on > IA-64, and KVM also works on PowerPC and s390, if that's a concern for > you. Xen generally uses paravirtualization with a modified kernel, > which can be a complication depending on your environment, although > with hardware extensions in the CPU it can also run unmodified guests. > KVM uses unmodified guests. Both allow for live migration. > > > From what I've seen, I would suggest that KVM would be the preferable > option to Xen. It offers slightly better guest performance, is built > right into the mainline Linux kernel tree, I know it allows resource > overcommitting and has GUI management tools (I believe Xen can also do > overcommitting, but I'm not as sure), and it appears to be what major > distributions are more interested in officially supported going > forward. > I've been using Xen for two years now at work and we've been rather happy with it. We've standardized on opensuse as our Linux distribution and that supports Xen out of the box. I have some friends at another company that have been rather happy with Xen on Debian and my coworkers out East use Xen on *BSD. I don't know if KVM can be hosted on other OSs, but that is nice if you prefer a BSD to Linux or want to switch at some point. -- Jon Schewe | http://mtu.net/~jpschewe If you see an attachment named signature.asc, this is my digital signature. See http://www.gnupg.org for more information. For I am convinced that neither death nor life, neither angels nor demons, neither the present nor the future, nor any powers, neither height nor depth, nor anything else in all creation, will be able to separate us from the love of God that is in Christ Jesus our Lord. - Romans 8:38-39