Hi, Dan Your suggested parameter is just protect for Dom0 memory freeing in balloon driver. (this parameter is just used in free()@xen/tools/python/xend/balloon.py) This parameter check is effective for Dom0 gives memory to other Domain. For this reason, xm mem-set & virsh setmem is not protected by your siggested parameter.(like setMemoryTarget@xxxxxxxxxxxxxxxxx). To protect Dom0 minimum memory size, Which component (Libvirt or Xend) should do? I think Sunou's solution is better one. Thanks Atsushi SAKAI "Daniel P. Berrange" <berrange@xxxxxxxxxx> wrote: > AFAICT, this is already guarded by XenD. In the /etc/xen/xend-config.sxp > file there is > > (dom0-min-mem 256) > > Is XenD perhaps no honouring this limit ?