A Virtual Solution

For Branham, joining VistaPrint in September 2005 was like “a trip back in time.” He had spent the eight previous years at Monster.com and had seen data center operations expand from one server to 1,000. He had spent the past year working on server virtualization. But Branham saw bigger challenges at VistaPrint. “From afar it looks like a print company. But once you get inside and see what’s really going on, it’s really a technology company,” Branham says, noting that everything from sales to manufacturing to shipping is run largely on custom-built software. “At Monster,” says Branham, “we weren’t anywhere near this data-focused.”

Like Monster in earlier days, VistaPrint wasn’t making the most efficient use of its data center. “They picked technologies that were right at the time, not right for where they were going.” Branham knew that virtualization would reduce power consumption. But Cebula knew that she wouldn’t convince anyone to spend more money on servers without a solid business case. So Branham ran the numbers, focusing on power expenditures.

Calculating the total energy consumption of a server isn’t straightforward. How much power a server consumes depends on how you use it. “It’s not something that our vendors talk about a lot,” says Cebula. The vendors were, nevertheless, able to provide data when asked. Using that information, Branham made the case for a greener data center crystal clear.

Branham calculated that if Vista­Print continued to use blades, this solution (conceived of as four racks housing eight IBM blade servers) would eat up approximately 32,000 watts (4,000 per server) and require 9.1 tons of air conditioning to cool. He estimated that the alternative, using eight HP Proliant DL 585 rack-mounted servers and 110 VMware instances, would require 5,500 watts (50 watts per virtual machine) and just 1.6 tons of AC. In addition, virtualization would enable VistaPrint to make better use of its CPU capacity. As is the case in many companies, VistaPrint was wasting additional energy by using only 20 percent of its server capacity. In a 24-hour period, the typical x86 server is used to only 5 percent or 10 percent of its capacity, says Gartner’s Kumar, while energy consumption even in idle mode is 60 percent to 80 percent of the energy consumed in use.

But the development team was concerned about stability and performance in a virtual environment. A year earlier, the IT group had attempted virtualization on the blades. Running VMware on the high-density hardware had been a bust. Memory limitations on the blades limited performance and the number of instances that could be run on each server. So when Branham used the “V”-word again, the development group got nervous. Branham won them over with a pilot project that proved the performance case. Swapping in the new servers in the Bermuda data center would mean eating the investment VistaPrint had made in the blades. But Cebula and the executive management team couldn’t argue with the ROI. Over three years, the greener solution would save VistaPrint $450,000—more than the cost of the hardware refresh.