Linux Guest Clock Runs Slowly on ESX Server 2 (1518)
Why does the clock in my Linux guest run more slowly than real time?
With ESX Server 2.5, you can increase the hardware clock interrupt rate to correct this problem. To do so, perform the following steps:
- Connect the VMware Management Interface to the ESX Server machine, and log on as root.
- Click the Options tab.
- Click the Advanced Settings link. This opens a new window with a list of configuration parameters.
- Scroll to the Misc.TimerHardPeriod parameter and click the current value. This opens a new window where you can update the value.
- Type a new value of 333, then click the OK button to exit.
Values other than 333 can only make the guest clock run too slow, not too fast. The period must be short enough to give the system frequent enough chances to check whether a virtual timer interrupt is due on the guest.
Neither ESX Server nor the guest need to be rebooted after changing TimerHardPeriod.
For additional information about timekeeping in virtual machines, see the following white paper Timekeeping in VMware Virtual Machines at www.vmware.com/pdf/vmware_timekeeping.pdf.