Virtual technology, real benefits

By Anne Stuart, June 2006

‘Virtualization’ may sound like the title of William Gibson’s latest futuristic thriller, but it’s actually a business technology whose time has come.

The approach is sort of an IT trick that can yield lots of tangible benefits focused on the efficient, highly flexible use of computing resources. At HP Labs, researchers are exploring virtualization as a method of creating real change in corporate data centers – which are, of course, notorious time and money guzzlers.

“At the highest level, our research is aimed at helping customers manage risk and cost,” says Tom Christian, a researcher based in Fort Collins, CO.

Christian and others at the lab are working to help make virtualization a widespread reality. They're exploring ways in which virtualization can streamline and add value to data-center operation, and contributing innovations to HP virtualization solutions. In addtion, they are participating in a groundbreaking industry-wide effort to develop standards and an open-source platform for the technology. (See "Introducing Xen.")

Efficiency and flexibility

What does virtualization do?

“Virtualization is a construct that allows you to provide an abstraction that’s different from the physical machine,” explains John Janakiraman, a Palo Alto, CA-based HP Labs researcher. “For example, it can make the computer system appear to have a lot more memory than it has.”

That opens the door to a whole new universe of computing capabilities, says Janakiraman: “We can make a physical machine look like many machines, or we can make many physical machines look like a single machine – and many other things in between,” he says.

Such capability lets organizations pool, share and reallocate their IT resources – manually at first, then automatically. data centers can, for instance, shift available processing power to where it’s most needed or quickly open up new storage space – and shut down machines that aren’t being used.

“You kill two birds with one stone,” Janakiraman says. “It allows you to run more applications on fewer machines, which improves efficiency, but you’re also getting more flexibility.”

Reducing risk

Virtualization reduces risk by creating redundancies, mirroring physical systems both to back up information and to provide an alternative if the physical system fails. At the same time, a single physical server can be securely divided into multiple virtual servers, isolating and shielding individual pockets of information as if they were stored on separate physical servers.

“Things can fail independently,” Janakiraman says. “One operating system can go down while another operating system on the machine continues to run.”

Virtualization also makes it possible to avoid application incompatibility problems by running them in separate, isolated virtual servers on the same physical server.

And while virtualization may sound complex, it actually simplifies matters: Because all those virtual servers share a common architecture and interface, researchers say, they can be easier to manage and maintain.

Developing industry standards

Not surprisingly, those tantalizing capabilities have prompted just about every major high-tech vendor (and many lesser-known ones) to launch virtualization initiatives.

What’s less predictable is that, in an effort spearheaded by HP, these otherwise-fierce competitors are collaborating to develop a standard industry-wide virtualization platform that will ultimately benefit all their customers.

“It’s one powerful tool,” Janakiraman says of that effort, known as Xen. “That’s why all these players are interested.”

Earlier efforts

Virtualization isn’t a new idea. “Thirty years ago, people were talking about ways to escape the physical machine,” Christian says. “Virtualization was commonly used to develop and test new architectures and software, an application for which it’s still well suited today. ”

In creating those virtual layers, researchers also realized they’d created that layer of protection Christian describes, providing a space to run programs they could isolate from the rest of the system.

Unfortunately, early virtual machines performed poorly, Christian says, running too sluggishly for widespread commercial use. But researchers convinced about virtualization’s vast potential kept experimenting with the concept.

“They realized that you can take some services, abstract them and provide access to them through a programmatic interface,” Christian notes, “and paravirtualization was born. There’s a lot of buzz about paravirtualization today, but only the word is new.”

These days, the performance of some benchmarks on virtual machines can approach the results seen on native hardware. Once the next-generation secure I/O hardware is available, performance of virtual machines should be, well, virtually identical to the real thing, Christian says.

Tapping unused resources

HP already offers a range of virtualization solutions and services. But there ’s more room for discovery.

HP Labs' work is focused on making corporate data centers more efficient. In a 2002 study, researchers found that most of the 1,000 servers in six corporate data centers were using only 10 to 35 percent of their available processing power. Virtualization can help a company tap that unused supply of computing capacity as needed to meet business demands.

A typical corporate data center has hundreds of machines running thousands of applications, with demand for those applications constantly fluctuating. Virtualization simplifies the adjustment of resources allocated to applications, enabling staff to meet demand changes in real time.

Current research is aimed at making such optimization happen automatically: resources are managed dynamically and transparently to deliver a contracted level of service to an application. Virtualization also offers applications the opportunity to participate in resource management.

“Applications can use the fact that they're running in a virtual environment to their benefit,” Christian explains. “For example, applications can return resources that aren’t going to be needed for awhile to the system to reduce operating costs, allowing that capacity to be reallocated elsewhere."

Other advantages

Meanwhile, virtualization can alleviate another data-center problem – high energy costs.

"One way you can save electricity is by turning things off," Christian notes. "You can do that if you have a model like virtualization that lets you compact your services to run on a minimum set of physical servers.”

Then there’s the need for high availability, which traditionally calls for having a second system and a cluster of servers ready to go on demand. Virtualization allows companies to quietly stash away similar computing capability until it’s needed. “That way,” Christian says, “you get high availability at low cost.”

Making it real

Several HP Labs projects are designed to help make virtualization a widespread reality. First, of course, there is their ongoing collaboration with others in the industry – including some competitors – to develop Xen, the common virtualization platform.

In addition, researchers are exploring options for automating virtual data center management.

“Right now, a lot of load-balancing is manual. A person has to initiate it,” Christian says. “The goal is to get people out of that equation to the extent that you can.”

But eliminating human intervention involves a critical social aspect – and a third area of emphasis for the research team: assuring those responsible for data center operations that the automated process is as trustworthy as possible.

“We haven’t quite reached the point where people are ready to relinquish control,” Christian says. “It’s like offering somebody a car that will drive itself in heavy traffic. Would you trust it?"

The researchers say the success of current virtualization technology has convinced people that virtualization is ready for the enterprise data center. The next step, they say, is automation, which will require earning the same degree of trust.

Researchers are focusing on locking in reliability, with the goal of building up users' trust and their confidence that the solution will work.

Virtual horizons

Researchers don’t hesitate to prognosticate about virtualization’s short- and long-term potential.

“It’s a key technology for the future, and it will become ubiquitous,” says Christian. He predicts that eventually, virtualization – with its obvious benefits for data centers – will be a standard firmware layer on every business IT system. “And you’ll see it even on your home machine,” he says, “where the isolation will be used to enable secure delivery of movies, music and other proprietary content.”

And Christian finds none of virtualization’s current capability – or its seemingly limitless potential – surprising.

“We’ve known all the time that it could do these things,” he says. “We’re just working on a common platform so that we can do even more.”