Everybody Loves Xen

by Timothy Prickett Morgan

The Xen open source virtual machine partitioning project is picking up momentum since acquiring the backing of venture capitalists at the end of 2004. Now, server makers and Linux operating system providers are starting to line up to support the project, contribute code, and make it a feature of their systems at some point in the future. Last week, it was commercial Linux distributor Novell's and chip maker Advanced Micro Devices' turn to back Xen.

David Patrick, general manager of Linux, open source, and platform services, said that Novell would be a contributor to the Xen project. IBM has been quietly contributing to Xen, and Hewlett-Packard announced at LinuxWorld last week that its HP Labs would also be contributing to the project. Both IBM and HP want to harden Xen so it can be used in commercial environments where security and stability are a given. IBM Research is contributing a security architecture called sHype and some code that it created for a home-grown X86 virtualization engine. HP is offering some code based loosely on ideas from its vPar virtual partitions for its HP-UX platform to help Xen better manage and secure Xeon partitions.

Novell's contributions to the project are unclear, but the company definitely wants to use Xen as a differentiator for its SUSE Linux distributions. Patrick said last week that Novell was putting software engineers on the Xen project and would be integrating it into the future SUSE Linux Professional 9.3 desktop. Patrick said that Novel tends to ship a new release of SUSE Linux Professional every six months or so, since it is the version of its Linux distribution that has all the latest-greatest features. SUSE Linux Professional 9.2 started shipping at the end of 2004, which means the 9.3 release is probably due mid-year or so. Patrick said that Novell is demonstrating Xen running on the LinuxWorld expo floor on SUSE Linux Enterprise Server 9, the current Linux 2.6 kernel version, and that Xen would be integrated fully into the future SUSE Linux Enterprise Server 10.

AMD also announced that it would be porting Xen to work with its Opteron processors and said further that it would have a commercialized version of the product available in the first half of 2005. Because of the direct memory architecture of the Opteron design, AMD believes that it will be able to do a better implementation of Xen. Moreover, AMD is counting on the "Pacifica" hardware virtualization features in future single-core and dual-core Opterons to help Xen run even better on the chips. Intel is creating a version of its "Vanderpool" virtualization hardware features for Pentium 4 processors, called "Silvervale," which will provide hardware-assist for virtual machine partitioning like that offered by Xen

Xen has really taken off since December 2004, when the leaders of the Xen project formed a corporation to sell and support Xen and they immediately secured $6 million from venture capitalists Kleiner Perkins Caufield & Byers and Sevin Rosen Funds. Xen is headed up by Ian Pratt, a senior faculty member at the University of Cambridge in the United Kingdom, who is the chief technology officer at XenSource, the company that has been created to commercialize Xen.