Computerworld — At the turn of the century, large data centers still relied mostly on direct-attached storage systems, which offer abysmal data utilization rates -- 25% to 30% of hard drive capacity.

Since then, many enterprise IT managers have at least begun to study technologies that could vastly improve data utilization, like Fibre Channel, IP storage-area networks, thin provisioning and virtualization. A recent survey by TheInfoPro found that almost half of Fortune 1,000 companies now use thin provisioning or plan to do so.

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Nonetheless, data utilization rates at most large companies remain at 40% or lower, resulting in a significant waste of electricity and floor space, analysts say.

"Most people I talk to don't even know how many terabytes of capacity they have on the floor, much less what the utilization is," said Andrew Reichman, an analyst at Forrester Research Inc.

Average storage utilization rates will remain in the 20% to 40% range until more IT managers start implementing the several storage management technologies available today, he added.

Over the past five years or so, thin provisioning, or provisioning only as much storage as an application server needs, has been among the most popular ways to boost IT storage utilization.

Slumberland Inc. has seen a significant improvement in data utilization since adopting the technology in 2004, said Seth Mitchell, an infrastructure team manager at the furniture retailer.

Since Slumberland installed arrays from Compellent Technologies Inc. with thin provisioning tools, the company's disk capacity utilization rate has reached 66%, Mitchell said. Without thin provisioning, the rate would hover around 30%, he estimated.

Texas Christian University, which rolled out a 3Par Inc. SAN with thin provisioning capabilities two years ago, has seen its data utilization rate increase to 50% of capacity, said Bryan Lucas, executive director of technology resources.

The university had previously used direct-attached storage systems, which Lucas said were easy to deploy and manage -- until the school's server farm began to grow. "The direct-attached model didn't scale well," he said.

Gartner Inc. (IT) analyst Adam Couture suggested that corporate implementations of thin provisioning technology have likely been slowed by a flagging economy.

Comprehensive storage monitoring and reporting tools can cost $250,000 to $1 million, Reichman said, and in many cases a full-time employee is needed to manage such a system.

This story was originally published in Computerworld's print edition. It was adapted from an earlier version that first ran on Computerworld.com.

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