20.19. Memory Balloon Device
A virtual memory balloon device is added to all Xen and KVM/QEMU guest virtual machines. It will be seen as
<memballoon>element. It will be automatically added when appropriate, so there is no need to explicitly add this element in the guest virtual machine XML unless a specific PCI slot needs to be assigned. Note that if the memballoon device needs to be explicitly disabled,
model='none'may be used.
The following example automatically added device with KVM
... <devices> <memballoon model='virtio'/> </devices> ...
Figure 20.67. Memory balloon device
Here is an example where the device is added manually with static PCI slot 2 requested
... <devices> <memballoon model='virtio'> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </memballoon> </devices> </domain>
Figure 20.68. Memory balloon device added manually
modelattribute specifies what type of balloon device is provided. Valid values are specific to the virtualization platform are:
'virtio'which is the default setting with the KVM hypervisor or
'xen'which is the default setting with the Xen hypervisor.