Facebook is bucking the trend toward server virtualisation and is interested in microservers for inexpensive growth and quick failover, the company's lab director said.
The social networking giant came out in support of Intel's plans for an expanded lineup of processors for microservers, as Gio Coglitore, director of Facebook labs, spoke at an Intel press briefing. At the event, Intel said it would introduce four new chips for microservers this year and in 2012, ranging from a 45-watt Xeon to an Atom-based processor with less than 10 watts of power consumption. All will have server-class features, such as 64-bit compatibility and ECC (Error-Correcting Code) memory.
Facebook has tested microservers in production and is interested in the architecture for its massive data centres, Coglitore said. The inclusion of those server features is key for the company to be able to use microservers, he said.
Microservers, a concept that Intel introduced in 2009, are small, low-power, one processor servers that can be packed into a data centre more densely than rack or blade servers. The microservers in a rack typically share power and cooling and may also share storage and network connections, said Boyd Davis, vice president of the Intel Architecture Group and general manager of data centre group marketing.
Manufacturers including Dell, Seamicro and Tyan have adopted the architecture, which has been most popular among large cloud service providers for large-scale, low-end hosting and web serving, according to Intel. The company expects microservers to remain about 10 percent of its server processor market.
Front-end web servers are where Facebook is nearly ready to start using microservers, according to Coglitore. "With Intel's announcement, it's just about to happen," he said. Facebook will probably start implementing microservers on a large scale beginning late this year or early next year.
Facebook uses a variety of server types across different parts of its data centres, but the company's aversion to virtualisation extends throughout its infrastructure, Coglitore said.
"We find in our testing that a realised environment brings efficiencies and brings the ability to scale more effectively," Coglitore said. "If virtualisation was the right approach, we would be a virtualised environment."
Facebook wants to be able to balance its computing load across many systems and potentially lose a server without degrading the user experience. "As you start to virtualise, the importance of that individual server is greatly enhanced, and when you have that at scale, it becomes very difficult," Coglitore said.
He prefers to think of computing units as faceless, interchangeable "foot soldiers." Virtualisation makes it harder to treat hardware resources that way, Coglitore said. Using a virtualisation software layer also tends to create lock-in, he said.
In addition, though Facebook could take advantage of more powerful server platforms for some functions, it sometimes turns to lower end systems for budgetary reasons. Facebook prefers to change servers every two to three years, following the chip refresh cycles of Intel and other processor makers, Coglitore said.
Intel currently ships a 45-watt Xeon and a 30-watt Xeon processor for microservers. Upcoming microserver chips include the 45-watt E3-1260L and 20-watt E3-1220L, which are already shipping to server makers, and a unnamed 15-watt part based on the new Sandy Bridge architecture. The Atom-based, sub-10-watt microserver processor coming next year also does not yet have a name, Intel's Davis said.