Additional parameters may be needed in the boot loader
(grub.conf) configuration file for certain operating system
variants after the guest is installed. Specifically, for optimal
clock accuracy, Linux guest boot parameters should be specified
to ensure that the pit clock source is
utilized. Adding clock=pit nohpet nopmtimer
for most guests will result in the selection of
pit as the clock source for the guest.
Published templates for Oracle VM include these additional
parameters.
Proper maintenance of virtual time can be tricky. The various
parameters provide tuning for virtual time management and
supplement, but do not replace, the need for an
ntp time service running within guest.
Ensure that the ntpd
service is running and
that the /etc/ntpd.conf configuration file is pointing to valid
time servers.