The balloon device is automatically added to qemu guests if supported, but it may be useful to desactivate it. The simplest to not change the existing behaviour is to allow <memballoon type="none"/> as an extra option to desactivate it (it is automatically added if the memballoon construct is missing for the domain). The following simple patch just adds the extra option and does not change the default behaviour but avoid creating a balloon device if type="none" is used. Daniel P.S.: there is also a XEN type uspposedly for xen but I was unable to find any baloon code in our current xen driver so no change there -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel@veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/