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Sun Microsystems VIRTUALBOX VERSION 3.1.0_BETA2 User Manual

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9 Advanced topics

dmidecode -t0

and the DMI system information can be obtained with

dmidecode -t1

9.16 Configuring the guest time stamp counter (TSC)

to reflect guest execution

By default, VirtualBox keeps all sources of time visible to the guest synchronized to a
single time source, the monotonic host time. This reflects the assumptions of many
guest operating systems, which expect all time sources to reflect “wall clock” time. In
special circumstances it may be useful however to make the TSC (time stamp counter)
in the guest reflect the time actually spent executing the guest.

This special TSC handling mode can be enabled on a per-VM basis, and for best

results must be used only in combination with hardware virtualization. To enable this
mode use the following command:

VBoxManage setextradata "My VM" "VBoxInternal/TM/TSCTiedToExecution" 1

To revert to the default TSC handling mode use:

VBoxManage setextradata "My VM" "VBoxInternal/TM/TSCTiedToExecution"

Note that if you use the special TSC handling mode with a guest operating system

which is very strict about the consistency of time sources you may get a warning or
error message about the timing inconsistency. It may also cause clocks to become
unreliable with some guest operating systems depending on they use the TSC.

9.17 Configuring the hard disk vendor product data

(VPD)

VirtualBox reports vendor product data for its virtual hard disks which consist of hard
disk serial number, firmware revision and model number. These can be changed using
the following commands:

VBoxManage setextradata "My VM"

"VBoxInternal/Devices/ahci/0/Config/Port0/SerialNumber"

"serial"

VBoxManage setextradata "My VM"

"VBoxInternal/Devices/ahci/0/Config/Port0/FirmwareRevision"

"firmware"

VBoxManage setextradata "My VM"

"VBoxInternal/Devices/ahci/0/Config/Port0/ModelNumber"

"model"

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