As virtualization technology gets increasing attention from large enterprises, the founder of the Xen open-source project said on Wednesday that Xen will develop more quickly compared to competitors, including Microsoft and VMware.
"Microsoft are very much in catch-up," said Ian Pratt, chief science officer for XenSource and professor at the University of Cambridge Computer Laboratory.
Speaking on the sidelines of LinuxWorld in London, Pratt said, "Xen has the advantage that there's a large development community who all are highly motivated to make Xen look good. That means that Xen does move really fast. Anything new that happens gets done on Xen first."
Pratt started the Xen project with his Cambridge University students four years ago. High interest in the project spawned a business, XenSource, which has created a virtualization product, XenEnterprise, based on open-source code.
By 2009, research company Gartner predicts, three technologies will dominate virtualization: VMware's ESX Server, Xen and Microsoft's Viridian hypervisor.
Xen has earned strong acceptance with vendors. Sun Microsystems is integrating Xen into Solaris 10. Xen is in Novell's recently released Suse Linux Enterprise Server 10 and will be in Red Hat's forthcoming Enterprise Linux 5.
Virtualization involves running multiple instances of an operating system on the same piece of hardware, such as a server. Studies show servers often run at 10 percent or less of their capacity, a figure that has declined as CPUs (central processing units) have become more powerful. Using virtualization can reduce the amount of hardware in the data centers, lowering energy costs.
While virtualization has become a hot buzzword, only about 6 percent of the x86 servers are using the technology, according to a study by TWP Research released in February. But Pratt predicts the figure will reach 100 percent.
Vendors continue to jump on the bandwagon. Microsoft's Viridian hypervisor, which the company is incorporating into its Longhorn server, has an "architecture heavily inspired on Xen design," Pratt said, meaning it's a high-performance hypervisor with a small code footprint. Hypervisor technology manages hardware resources to allow multiple operating systems to run in isolation on the same hardware. The final version of Viridian is due about six months after the release of Microsoft's Windows Longhorn server.
While they are competitors, Microsoft and XenSource agreed in July to make the next version of Windows Server compatible with Xen-based guest operating systems. Microsoft also agreed to offer technical support for instances of Windows running as guest on XenSource's XenEnterprise.
One of the next targets for the Xen project is developing what's called "paravirtualization" -- refining the interface between the hypervisor and the operating system and how it uses resources of the underlying hardware, Pratt said. The advantage is better performance.
"It's much better to tell an operating system you have 256M bytes of memory rather than telling it its got 512 M-bytes and trying to fake out the extra 256 [M-bytes] and swapping things to and from disks," Pratt said.