Google, Microsoft spark interest in modular data centers, but benefits may be exaggerated

Interest in modular data centers is growing, fueled by high-profile endorsements from Microsoft and Google. But the model raises new management concerns, and efficiency claims may be exaggerated.

Modular, containerized data centers being sold by vendors such as IBM, Sun and Rackable Systems fit storage and hundreds, sometimes thousands of servers into one large shipping container with its own cooling system. (See photos in our related slide show.) Microsoft, using Rackable containers, is building a data center outside Chicago with more than 150 containerized data centers, each holding 1,000 to 2,000 servers. Google, not to be outdone, secured a patent last year for a modular data center that includes "an intermodal shipping container and computing systems mounted within the container."

To hear some people tell it, containerized data centers are far easier to set up than a traditional data center, easy to manage and more power-efficient. It should also be easier to secure permits, depending on local building regulations. Who wouldn't want one?

If a business has a choice between buying a shipping container full of servers, and building a data center from the ground up, it's a no-brainer, says Geoffrey Noer, a vice president at Rackable, which sells the ICE Cube Modular Data Center. 

"We don't believe there's a good reason to go the traditional route the vast majority of the time," he says.

But that is not the consensus view by any stretch of the imagination. Claims about efficiency are over-rated, according to some observers.

Even IBM, which offers a Portable Modular Data Center and calls the container part of its green strategy, says the same efficiency can be achieved within the four walls of a normal building.

IBM touts a "modular" approach to data center construction, taking advantage of standardized designs and predefined components, but that doesn't have to be in a container. "We're a huge supporter of modular. We're a limited supporter of container-based data centers," says Steve Sams, vice president of IBM Global Technology Services.

Click to see: Rackable Systems’ ICE Cube portable data center can be fitted with as many as 22,400 processing cores in 2,800 servers.

Containers are efficient because they pack lots of servers into a small space, and use standardized designs with modular components, he says. But you can deploy storage and servers with the same level of density inside a building, he notes.

Container vendors often tout 40% to 80% savings on cooling costs. But according to Sams, "in almost all cases they're comparing a highly dense [container] to a low-density [traditional data center]."

Containers also eliminate one scalability advantage related to cooling found in traditional data centers, according to Sams. Just as it's more efficient to cool an apartment complex with 100 living units than it is to cool 100 separate houses, it's more cost-effective to cool a huge data center than many small ones, he says. Air conditioning systems for containerized data centers are locked inside, just like the servers and storage, making true scalability impossible to achieve, he notes.