8.10.4. frequency, mode, and present
The
frequency
attribute is used to set a fixed frequency, and is measured in Hz. This attribute is only relevant when the name
element has a value of tsc
. All other timers operate at a fixed frequency (pit
, rtc
).
mode
determines how the time source is exposed to the guest virtual machine. This attribute is only relevant for a name value of tsc
. All other timers are always emulated. Command is as follows: <timer name='tsc' frequency='NNN' mode='auto|native|emulate|smpsafe'/>
. Mode definitions are given in the table.
Value | Description |
---|---|
auto | Native if TSC is unstable, otherwise allow native TSC access. |
native | Always allow native TSC access. |
emulate | Always emulate TSC. |
smpsafe | Always emulate TSC and interlock SMP |
present
is used to override the default set of timers visible to the guest virtual machine..
Value | Description |
---|---|
yes | Force this timer to the visible to the guest virtual machine. |
no | Force this timer to not be visible to the guest virtual machine. |