Applying Virtualization - Oracle Solaris 10 System Virtualization Essentials - page 271

a domain (dom0 or domU). It is useful in reclaiming unused memory or
allocating additional memory within a domain. Reclaiming unused memory
is called a balloon down event . Not all domain memory is available to be
reclaimed, however. For example, the memory may be in use.
When dom0 starts, the kernel allocates many structures related to the size
of the available memory. If a large amount of memory is available, then
these structures will consume more memory. If a balloon down event occurs
for dom0, those structures cannot be freed; thus that memory is wasted.
Furthermore, if the hypervisor tries to reclaim domain memory below the
level at which memory in use would be affected, then the operation will fail,
which will affect system performance.
If the mem setting shown earlier is applied, dom0 will see only 1 GB RAM.
The remaining memory can then be used for guests.

4. Ve r i f y t h a t t h e n e w b o o t e n v i r o n m e n t i s s e t .

# /usr/sbin/bootadm list-menu
The location for the active GRUB menu is:
/rpool/boot/grub/menu.lst
default 1
timeout 30
0 OpenSolaris 2009.06
1 xVM hypervisor

The entry number listed as the default menu item should correspond to the
menu item for the xVM hypervisor. In this case, the default menu item is
number 1, and that menu item is xVM hypervisor . As a consequence, the
xVM hypervisor will be booted by default.
If the hypervisor does not boot, change the default menu item by running the
following command:

# /usr/sbin/bootadm set-menu default=1

5. Reboot into the new boot environment.

# /usr/sbin/reboot

6. Start and check the xVM hypervisor services.

# /usr/sbin/svcadm enable -r xvm/virtd ; svcadm enable -r xvm/domains
# /usr/bin/svcs -a|grep -i xvm
disabled 14:28:42 svc:/system/xvm/ipagent:default
online 14:28:40 svc:/system/xvm/vnc-config:default

continues