In 2001, VMware delivered its first virtualisation products for x86 servers, setting off what has become one of today's biggest tech trends. But the benefits of virtualisation, particularly its ability to allow users to rapidly provision new workloads, are pushing demand for storage to new highs.

Just over half of all workloads in a data center are now virtualised, a milestone that was hit this year, according to Nemertes Research, which benchmarks data collected from user organisations.

78 percent of all workloads will be virtualised eventually

Ted Ritter, an analyst at Nemertes, believes that about 78 percent of all workloads will eventually be virtualised. The remaining workloads will continue to run on dedicated physical servers because of security and compliance issues, or in some cases because the software vendor doesn't yet support virtualisation.

Another reason for keeping workloads on a dedicated physical server is for performance, such as that needed by high-speed trading applications. In those cases, users see no benefit to virtualisation "because it adds some delay to the mix," said Ritter.

He presented new findings on virtualisation deployment at the Afcom data center conference here.

Applications can be provisioned in a flash

In the pre-virtualisation days, the process for requisitioning server space often required review by IT administrators. But virtualisation "removes a lot of the natural friction in a data centre. Now you can provision a new application in minutes, versus days, weeks, months," said Ritter.

This capability is pushing up storage demand about 40 percent a year, a figure that was developed from data from 240 companies, Ritter said.

IDC reported earlier this month that in the second quarter of 2011, the total market for disk storage systems grew by just over 10 percent.

Virtualisation sprawl, said Ritter, "is eating up storage left and right."

Users such as Kyle Gerlach, a data center engineer at a company he didn't want identified, is dealing with this trend. "We definitely have seen a large amount of storage growth as we virtualise more," he said.

Hungry, hungry servers

So far, Gerlach added, his company has been able to stay of ahead of the problem. While storage needs are growing increasing, his firm is seeing "massive power savings" with server virtualisation, particularly as it moves workloads to more power-efficient systems.

Gerlach said his company has also started using a data deduplication system "which is reclaiming a lot of that virtualisation sprawl."

IT organizations are responding in multiple ways to this trend, said Ritter, such as placing tighter controls on new virtualisation deployments.

Even so, data centers are running up against power limitations as they add storage and move to power-demanding blade servers as their virtualisation platforms, said Ritter.

"We see virtualisation, storage growth [and] power density limitations pushing organizations in the direction of outsourcing," said Ritter.

In particular, the use of co-location facilities grew 20 percent between 2010 and 2011, said Ritter.

Wayne Ebersole, a strategic business manager with a data center design firm he asked not be named, said demand for data center space and power is rising so rapidly that customers "have a difficult time knowing exactly what their IT requirements are. Freezing the design is the difficult proposition."