Second helpings

Being constantly aware of dipping storage levels is one potential drawback of thin provisioning. "The only real issue that users need to consider is having to monitor the 'free space' available in their systems and not let that drop below acceptable levels. Free space is the amount of capacity in a system that has not been allocated to logical volumes," says Stanley Zaffos, an analyst at Gartner.

Also, because users aren't allotted their full share of storage upfront when thin-provisioning strategies are in play, senior executives might get some pushback from systems administrators.

"Definitely, IT managers are a suspicious lot - in part because they've had many weekends ruined when there are problems with critical systems. So they tend to be risk-averse," says Brian Doerr, chief technology officer at Savvis, a provider of managed and outsourced IT services. Savvis has incorporated 3PAR's thin-provisioning capabilities internally to make sure it can meet customers' storage needs. The outsourcer also extends thin-provisioning options to its own clients.

Though a certain degree of vigilance is required when using thin-provisioning software, skittishness that users will be left without enough storage is probably unwarranted. "Fears surrounding the deployment of storage that supports thin provisioning have proved mostly unfounded," Zaffos says. Most experts agree that storage hogging is a much bigger problem than is the monitoring of storage levels or even the unlikely event of temporarily running short on space. "We don't want to promise a lot of storage to our users out there, because they will find a use for it. There may have been a little bit of concern among these users initially that storage would run out, but we just tell them that we have enough storage to last six to seven months and that for x amount of dollars we can purchase more," Haas says.

Indeed, thin provisioning can help users become more realistic about their storage needs, because they are no longer faced with getting all of their capacity upfront or not at all. "Thin provisioning improves the relationship between operations and its customers, because the technology allows users to continue requesting more storage," Zaffos says. "It's always easier to say yes than to explain to users why they do not need what they want."

Better things to do

Most experts agree that users shouldn't be left to dream up ways to use all of the storage space at their disposal, nor should they have to fret over the prospect of running out of capacity. "A scientist should never have to worry about how much storage space they have available," says Peter Herrin, a systems analyst at Infinity Pharmaceuticals, a cancer drug discovery and development company.

Infinity installed 3PAR's InServ S800 storage server in January 2003. Like Ask.com, Infinity made use of the vendor's Thin Provisioning and Virtual Copy options, which took the burden off Infinity officials who were constantly trying to ensure that drug researchers would have enough storage. "The real trick as far as storage projection goes is priming the pipeline as a particular drug moves from the research to the clinical trial stage," says John Keilty, Infinity's director of informatics. "Our challenges surround both the volume of data we have and its complexity. For instance, when researching a particular drug, a scientist can be working with hundreds of thousands of molecules that make up a protein associated with a certain type of cancer. This means millions of data points. Storage issues are further complicated by the fact that we must accommodate many, many images of these molecules, so we are talking terabytes of data."

Though not always as dramatic as the storage needs of researchers pursuing new cancer treatments, users in many vertical industries truly require vast volumes of capacity to help accomplish their company's mission. Yet how fast must this space be made available? This is a key question to fend off storage hogging, experts agree.

Pressing for answers to such questions and using the thin-provisioning options now on the market can keep storage-hungry project managers and business units from piling their plates full only to leave chunks of capacity untouched. These strategies will also let company officials avoid having to resort to mothers' "starving children in China" arguments to prevent users from staking claim to more storage than they'll ever use.