The energy consumed by data centers around the world, according to some estimates, will reach 2 trillion kilowatts per hour by 2020. Data centers consume about 2% of all power used worldwide. But several trends are converging to make data centers, the engines behind corporate IT, more efficient and less energy draining. Server, storage and network virtualization and the movement of some computing tasks to public clouds are helping reduce data center power needs. And forward-thinking data center managers are letting temperatures rise in their facilities as high as 85%, enabling dramatic savings.
Since the completion of the Wells Fargo-Wachovia merger in February of this year, server virtualization and data center efficiency have replaced integration issues as top IT priorities for the San Francisco bank. In the past few years the $1.3 trillion-asset bank, under the leadership of Jim Borendame, executive vice president and head of compute platform services, has deployed server consolidation and virtualization, de-duplication, and desktop and power management to reduce energy use, while also reducing the number of satellite data center locations. He plans to close 12 data centers over the next couple of years.
In 2008, the bank opened a power and thermal optimization lab to test how it can use equipment more effectively to save space and power and improve server and storage utilization. "We've given our storage engineering team quite a bit of feedback on how they are consuming storage on a per-terabyte basis," Borendame says. "Right now, I can get 178 terabytes in a square foot, and have increased the power efficiency of that footprint by 85%." In the previous generation of technology, a mere 93 terabytes could be stored per square foot.
The bank is not using super high-end equipment - it's got standard Hitachi, EMC and NetApp storage devices -- but it's engineering and configuring the machines in a way that drives utilization up. "We've also lifted the utilization of our storage -- we're now using more of the available capacity through provisioning and leveraging some of the virtual storage mapping capabilities," he says. "We've found a quirk of VMware -- people tend to over-allocate virtual CPUs and virtual memory." In other words, they ask for more computing resources than they need. The bank uses the reporting and analytics in VMware's vCenter to find these discrepancies and trim back, and reaps substantial increases in capacity and performance in VMware, Borendame says.
By using de-duplication (a method of reducing storage needs by eliminating redundant data), the IT team has been able to load up storage arrays. "It's extremely effective; it's helped us change our hardware configurations in noticeable ways," Borendame says.
The bank has also been steadily getting more work out of its servers. "In 2011, for every physical server we installed, we took out 2.8 physical servers on average, which is a big deal," Borendame says. "Just in the month of April, we took out 816 servers."
Before a server is refreshed, IT staff take a good look at whether or not that server is still needed, he says. "If the server is physical, we do everything we can to take it to a virtual environment." About 80% of new servers at Wells Fargo are virtual servers. The bank's overall server virtualization rate is about 38%.
Pre-merger, power consumption for the Wachovia and Wells Fargo data centers was growing 17-19% annually. "We've been able to go to zero and we're starting to shrink the footprint," Borendame says.
Because the data centers represent about 15-17% of the power bill of the entire company, "when you stop growing like that, you help the whole company in its green mission," Borendame says. "This year we'll be at zero to negative growth in our data centers." In 2009, Wells Fargo promised to reduce its overall greenhouse gas emissions by 20% within 10 years. At the end of 2011, the company had already achieved a 12% reduction, so on Earth Day Wells Fargo announced that its new corporate goal is 35%.
One effort that's helping is the bank is targeting a temperature of 80 degrees Fahrenheit in its core regional data centers. "We're not planning to do it outside of that space because it's not easy to manage in small spaces," Borendame says. Today, a couple of the data centers run at 75 degrees. "We've asked them to do it very slowly so that we don't create thermal stress in the electronics," he says. "I'm very comfortable that we'll be able to operate at 80 degrees." In fact, some new technologies the bank has installed in the past couple of years can operate in the 90 to 100 degree range.
The risk of running higher temperatures, in Wells Fargo's experience, is not so much electronic breakdowns but material changes, such as problems with insulation, wiring and connectors. Some older connectors, for instance, will corrode as temperatures get higher.