A show of hands at yesterday's Datacenter Dynamics conference in New York found that about 10 percent of attendees had implemented liquid cooling for high-density blade server installations. How many are considering it? That's when easily half the audience members put their hands up.
That's why cooling has been the hot topic at industry conferences the past two weeks, with vendors positioning water and/or refrigerant systems as the only viable solution to ever-increasing heat loads in data centers. That's not always an easy sell to data center managers who are wary of bringing fluids into the data center - much less into the rack with the equipment.
"Do you have hydrophobia? If you've got hydrophobia, get over it," Richard Sawyer, Director of Data Center Technology for American Power Conversion (APC), said in a presentation last week at Data Center World in Atlanta. "Plan for fluids in your data center. It may be a fluid refrigerant, or it may be water. But get used to it."
"It's something that is inevitable," Herb Villa, Field Technical Manager of Rittal Corp, said Tuesday at the DataCenter Dynamics conference in New York. "We understand the reluctance. But ultimately, customers will have no choice."
The pace and timing of that transition will vary widely from company to company. While some facility managers are dealing with short-term cooling challenges, those with substantial space available in their data centers have more time to study their options and learn from the early adopters.
Cooling vendors began discussing the need for fluid-based solutions as early as 2002. "At that time, there were a lot of doubters," said Russ Hoppes, a regional manager for Liebert Corp., a unit of Emerson Network Power. "Over time, it's reached the point where most customers are dealing with hot spots of some kind."
Liebert's line of XD products - shorthand for "extreme density" - use a refrigerant-based system housed in cooling units that attach to the top of a standard 7-foot, 42-inch rack. The XD units are currently being used in more than 100 installations. Rittal and APC each offer water-based cooling units fitted as an environmentally controlled chamber on the side panel of a server rack.
New low-power processors being developed by Intel and AMD may affect the timelines for the transition to fluid cooling, according to several speakers at DataCenter Dynamics. But that's only delaying the inevitable, as other components of blade servers will soon need more juice. Next-generation blade servers will require more memory, and more power for that added memory, according to Scott Tease, IBM's Worldwide Blade Center Project Manager.
"Ultimately the problem is just that we're running out of cold air," said Rittal's Villa. "You can only push so much air through a 2-foot by 2-foot perforated tile."