Simon Crosby just posted a blog announcing that Citrix is Open Sourcing the VHD support , their implementation of the of the Microsoft VHD virtual hard disk format to the Xen community for inclusion in the open source code base.
VHD is what XenServer uses to store file-based images, and according to Simon this code is considerably more robust and efficient than the qcow implementation that is in the tree today.
Simon lists different reasons for doing this
First the various Xen implementations from the Linux vendors vary wildly in their support for virtual hard disk images, and the performance of their implementations.
Thus far we have yet to see any good implementations of VHD in the Linux vendor category. Cluttering users’ storage with raw image files without any of the benefits of the built-in capabilities for snapshotting, cloning etc that are fundamental primitives in any production virtualization environment, is just a bad idea. ,
Second, since the majority of VMs will be in the VHD format in future, we want to enable the ISV ecosystem to adopt the format and quickly deliver a rich set of add-on capabilities that allow users to be more productive in their virtual environments. VHD is more than just a VM format used by Hyper-V – it’s a delivery format from Microsoft for future versions of Windows. The format is documented publicly and the specification is available under the Microsoft Open Specification Promise program.
And to finish of he hopes the free implementation of the VHD format will accelerate the adoption of Windows in the cloud, I`m wondering how people plan on manage their Licence sprawl, but that’s just me 🙂
So which Virtualization vendor didn’t announce they would be Open Sourcing anything yet this year ? 🙂