[root@a4 xen3]# vgchange -ay
  device-mapper ioctl cmd 9 failed: Cannot allocate memory
  Couldn't load device 'vmspace-a41'.

  device-mapper ioctl cmd 9 failed: Cannot allocate memory
  Couldn't load device 'vmspace-a51'.
  17 logical volume(s) in volume group "vmspace" now active
