Red Hat announced several moves on Tuesday to bring virtualisation to the mainstream Linux market by the end of the year, a move that the company promises will dramatically increase server efficiency.
The company already has promised to include a major virtualisation component, the Xen hypervisor software, in its next premium product, Red Hat Enterprise Linux version 5, due by the end of the year. But Tuesday, executives gathered in San Francisco to detail some steps leading up to that milestone.
Among those milestones are test versions of Linux with full Xen support, a customer pilot programme, Red Hat services for technology assessment and migration, a Web site with various educational materials, the Libvirt library of reusable virtualisation-related software, and an effort to stabilise interfaces used to control Xen.
Increasing efficiency by running multiple operating systems on one computer is a decades-old technology, but it's now coming to market for mainstream x86 servers. Intel and AMD — two Red Hat partners — are adding features to their processors to improve virtualisation performance and abilities. And Xen's virtualisation software provides a foundation for multiple operating systems, thereby letting a single system replace several that spend much of their time idly.
"If, historically, server utilisation is less than 20 percent and our approach can drive to 80 percent, obviously there are tremendous savings not only in terms of hardware, but also in space, power, cooling, and system management costs," said Red Hat's chief technology officer, Brian Stevens.
Red Hat expects Xen to become much more widespread testing with the release of Fedora Core 5, scheduled for Monday. Its predecessor, Fedora Core 4, included Xen, but only in a primitive form that required experienced programmers to hand-assemble numerous components.
"Fedora Core 4 was the anti-integrated thing," Stevens said. But with Fedora Core 5, he said, the priority is on "How do we get it into the hands of the masses?" To that end, it supports Intel's virtualisation technology and will support AMD's when it arrives.
The next step will take place this summer, when the company releases the RHEL 5 beta, said Tim Yeaton, executive vice-president for enterprise solutions at Red Hat.
Xen's slow progress
Xen has widespread support among server and processor companies, but the software has taken longer to become established than Red Hat hoped, Stevens said. In particular, the company had wished Xen to be part of the mainline Linux kernel overseen by Linus Torvalds. That would have given Red Hat an easier time keeping its source code branch synchronised with the main Linux software tree.
"It's not going as fast as we want. We have weekly calls with the Xen guys. They're making progress," Stevens said. "It's a little frustrating. It means now we have to deliver something out of tree. We're bearing the pain. We didn't want to go to RHEL 5 with [Xen] unintegrated, but it seems like that's going to be the case."
The problem was simply that the Xen software is in flux. "The code base is churning like crazy. Trying to merge something that's evolving so fast is the hard part," Stevens said. He still believes Xen will be merged with the mainline kernel this year, though Red Hat has to use an earlier version in RHEL 5 — probably version 2.6.17 — to allow time for testing before the product is released.
Thumbs up for OpenVZ Running multiple operating systems is Red Hat's first virtualisation goal, but the company also is interested in another method that divides a single instance of an operating system so it looks like several. The idea, embodied by Sun's Solaris Containers, is being brought to Linux with SWsoft's OpenVZ.
"We see a strong use case for lightweight container-based virtualisation. The hard part is to get that enablement capability in side Linux itself," Stevens said. Linus Torvalds has begun accepting some early changes required to permit the software, he said, but Red Hat spokeswoman Leigh Day said the company doesn't expect it to arrive in RHEL 5.
A start-up called XenSource employs several primary Xen programmers and is working to commercialise the software. In February, XenSource announced a new management team and business approach, and the change yielded an endorsement from Red Hat on Tuesday.
Red Hat doesn't yet have a business relationship with XenSource, Stevens said in an interview. But, he added, "We'd love to see one. We're expecting there will be a partnership relationship with them — we just don't know what it will be."
