Daniel de Kok wrote on Mon, 15 Oct 2007 14:45:22 +0200:
It depends on what you want to run as a domU. Paravirtualization is very fast (e.g. for running domU CentOS 4/5 kernels). On the other hand, some devices are very slow if you use Xen HVM for running systems that do not have a kernel that functions as a Xen domU. As long as we don't have paravirtualized network/display drivers for those systems, network/graphic performance will not be very good.
So, what do you plan to run as a virtual machine?
Strictly CentOS 5. CentOS 5 host and CentOS 5 guest. The testing machine doesn't have a CPU with virtualization support, so they will run paravirtualized. The most likely production machine I want to put Xen on has an X2 from last year (X2 3800+ EE because of temperature in a 1U box) where I'm not sure if it might support virtualization, but I plan to do paravirtualization, anyway. Usage will be for web/mail server related tasks (especially heavy MySQL usage with several GB databases), no desktop and no fileserver tasks. There will be only two or three DomUs.
Did you try to connect to the VM virtual framebuffer with vncviewer, rather than virt-manager? What loads do you get then?
I didn't know I can do that. I haven't enabled vncserver on the host machine as I couldn't really get it going, if I want to VNC in I connect to the vino-server that's automatically coming with Gnome. Would this allow me to connect to the VM frame buffer as well? On the production machine I wouldn't be using/installing Gnome at all. But for getting acquainted to the stuff it's much easier to install and manage a new VM with virtual machine manager.
Kai