xml file elements and attributes of VBox version 4
Posted: 22. Feb 2011, 10:24
My first questions I have are regarding the elements
HardwareVirtEx
and
HardwareVirtExVPID
located under the <CPU> element of the <Hardware version="2"> element of the VM's xml file.
I would like to know what they reference.
Background: I had a fresh install of VBox version 4.0.2 where I created a new VM(*) and attached a VDI which was created in version 3.x.x. I have since then updated to 4.0.4
I had several VMs with corresponding VDIs created with version 3.x.x. I had updated VBox to version 4.0.4 and made copies of them, including the VirtualBox.xml (this was on the same host but using a different image on the host (clonezilla backups, I have several images for my host.)) Being lazy (efficient with resources) I decided to add a Windows VM (standard Widows installation to save time when creating VMs to avoid having to install Windows every time) and a Linux VM by simply adding them to the current VirtualBox.xml and of course copying the VM-xml files to the .VirtualBox\Machines folder and the VDIs to the .VirtualBox\HardDisks folder. Nothing spectacular, everything works fine. (Note: this was done AFTER posting the issues in the Discuss the 4.0.4 Release thread regarding hanging of the VM and the restart issues.) The VDI used to create the new VM(*) was the same VDI as the VM of a standard Windows installation at the time of creation.
Upon comparing the two xml files I noticed that there is an additional attribute for the HardwareVirtEx element named exclusive. This must be a new attribute which was not available in previous versions. After reading the on-line manual it is written there, "It will only silently upgrade the settings format if the current settings cannot be expressed in the old format, for example because you enabled a feature that was not present in an earlier version of VirtualBox,...". My question here is, why wasn't it updated? (This question can be asked regarding other newer elements or attributes such a HID and HPET or IOCache.) The way I see it, as the attribute or element didn't exist in the previous version, it couldn't be expressed as such and should be updated.
Regarding HardwareVirtExVPID, my question (in addition to knowing what it references) is, why is the attribute enabled="false" in the older VM and enabled="true" in the newer VM?
Both VMs have the exact same settings regarding CPUs, RAM, NAT, Display VRAM etc.
The next question I have is regarding the Memory element and the attribute PageFusion (which, by the way is also only in the newer VM) also located under the <Hardware version="2"> element of the VM's xml file. What does PageFusion reference?
Like I said, the added VMs haven't caused any issues, they run smoothly. I am just trying to understand the implications of the differences in the xml file formats and why they are not updated.
Thanks in advance for taking the time to clarify this for me.
HardwareVirtEx
and
HardwareVirtExVPID
located under the <CPU> element of the <Hardware version="2"> element of the VM's xml file.
I would like to know what they reference.
Background: I had a fresh install of VBox version 4.0.2 where I created a new VM(*) and attached a VDI which was created in version 3.x.x. I have since then updated to 4.0.4
I had several VMs with corresponding VDIs created with version 3.x.x. I had updated VBox to version 4.0.4 and made copies of them, including the VirtualBox.xml (this was on the same host but using a different image on the host (clonezilla backups, I have several images for my host.)) Being lazy (efficient with resources) I decided to add a Windows VM (standard Widows installation to save time when creating VMs to avoid having to install Windows every time) and a Linux VM by simply adding them to the current VirtualBox.xml and of course copying the VM-xml files to the .VirtualBox\Machines folder and the VDIs to the .VirtualBox\HardDisks folder. Nothing spectacular, everything works fine. (Note: this was done AFTER posting the issues in the Discuss the 4.0.4 Release thread regarding hanging of the VM and the restart issues.) The VDI used to create the new VM(*) was the same VDI as the VM of a standard Windows installation at the time of creation.
Upon comparing the two xml files I noticed that there is an additional attribute for the HardwareVirtEx element named exclusive. This must be a new attribute which was not available in previous versions. After reading the on-line manual it is written there, "It will only silently upgrade the settings format if the current settings cannot be expressed in the old format, for example because you enabled a feature that was not present in an earlier version of VirtualBox,...". My question here is, why wasn't it updated? (This question can be asked regarding other newer elements or attributes such a HID and HPET or IOCache.) The way I see it, as the attribute or element didn't exist in the previous version, it couldn't be expressed as such and should be updated.
Regarding HardwareVirtExVPID, my question (in addition to knowing what it references) is, why is the attribute enabled="false" in the older VM and enabled="true" in the newer VM?
Both VMs have the exact same settings regarding CPUs, RAM, NAT, Display VRAM etc.
The next question I have is regarding the Memory element and the attribute PageFusion (which, by the way is also only in the newer VM) also located under the <Hardware version="2"> element of the VM's xml file. What does PageFusion reference?
Like I said, the added VMs haven't caused any issues, they run smoothly. I am just trying to understand the implications of the differences in the xml file formats and why they are not updated.
Thanks in advance for taking the time to clarify this for me.