Temperatures in Phoenix, Arizona - one of the most arid places in the US - routinely exceed 100 degrees Fahrenheit (38 degrees Celsius). That's about the opposite of the typical cool-weather environments companies often choose to build data centers.
But in about two weeks, eBay will formally open its latest data center there, a facility the company hopes will be used for as long as 20 years.
"Who would want to build a data centre in Phoenix?" asked Mike Lewis, director of eBay's Mission Critical Engineering. "Yes, it's hot."
EBay already has a facility next to the latest data center, which was a project "Mercury," said Lewis, who spoke at the DatacenterDynamics conference in London on Wednesday.
It started with a two-floor warehouse that was intended to store and test equipment for the existing Tier 4 data centre next door. But that facility was filling up, "so we decided may we will turn this [warehouse] into a Tier 2, lower-cost facility," Lewis said. Staff from the existing data center would run both facilities.
Lewis said eBay wanted to build a facility that could be quickly expanded with minimal impact on the company's operations. It wanted parts of the data center to be different tier categories. It also wanted it to be as dense as possible, with the ability to place containers containing server racks on the roof and get those containers running within 24 hours.
Six megawatts to Twelve megawatts
EBay put out 50 requests for proposal and received 17 responses, which Lewis described as harnessing talent and brain power "for a problem honestly we didn't know how to solve."
The company's selected contractors came up with a design for a six-megawatt facility that would could be upgraded to 12 megawatts, with an ability to increase that capacity in two- megawatt increments, Lewis said. It has about 7,000 square feet of main server space, with 7,000 square feet of space for containers on the roof.
To speed up deployment of new server racks, eBay has been working with vendors and rack manufacturers on a concept Lewis called "rack and roll."
Rather than eBay doing the early configuration work, it is ordering racks to specification, where a vendor fills the rack with servers, does all of the cabling and labeling and loading of the OS. Then it goes to eBay, which can have it configured with its own applications within four hours.
"Literally, they ship us the whole rack of servers," Lewis said. "It's literally ready to go within minutes of it showing up on the dock."
The facility is also capable of free cooling year round in Phoenix despite the city's notorious heat, Lewis said. The facility has an oversized cooling tower that runs a condenser water loop system underneath the floor.
Using new energy-saving measures
"We are able to get 85-degree water [Fahrenheit] in Phoenix 24/7," Lewis said.
Lewis said the condenser water that was open to the air isn't directly used, but instead run through a heat exchanger, which shaves off a couple of degrees. On the warmest days, the system can deliver 87-degree water "anywhere on the floor, anytime, and the majority of the year it's much better than that," Lewis said.
Other energy-saving measures employed include the use of LED lights, Lewis said. Photos of the facility under construction are posted on Data Center Pulse, a nonprofit industry group.
EBay is shooting for a low Power Usage Effectiveness figure, which is a ratio that compares the total power used by a facility to the power used by its equipment. The lower the number, the better. Not long ago, data centers routinely had PUEs of 2.0 or higher, but new custom-built ones are below 1.5
Lewis said eBay would like its latest center to have a PUE of 1.1. Although the center is running, Lewis said his boss would not let him release the figure. It was marked "confidential" on his slides. But he expects the figured to be released when the data center is formally opened in a couple of weeks.
"Unfortunately for you guys, I apologise," Lewis said to attendees.