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8.10.5. Examples Using Clock Synchronization

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Example 8.5. Clock synchronizing to local time with RTC and PIT timers

In this example. the clock is synchronized to local time with RTC and PIT timers
<clock offset="localtime">
	<timer name="rtc" tickpolicy="catchup" track="guest virtual machine" />
	<timer name="pit" tickpolicy="delay" />
	
</clock>

Note

The PIT clocksource can be used with a 32-bit guest running under a 64-bit host (which cannot use PIT), with the following conditions:
  • Guest virtual machine may have only one CPU
  • APIC timer must be disabled (use the "noapictimer" command line option)
  • NoHZ mode must be disabled in the guest (use the "nohz=off" command line option)
  • High resolution timer mode must be disabled in the guest (use the "highres=off" command line option)
  • The PIT clocksource is not compatible with either high resolution timer mode, or NoHz mode.
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