# virsh qemu-monitor-command --hmp vmname 'info kvm'
kvm support: enabled
# virsh qemu-monitor-command --hmp vmname 'info balloon'
balloon: actual=1024
# virsh qemu-monitor-command --hmp one-300 'info balloon' balloon: actual=2048 # virsh qemu-monitor-command --hmp one-300 'balloon 1024' # virsh qemu-monitor-command --hmp one-300 'info balloon' balloon: actual=1024