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Your Facebook Data Is Stored Inside This Beautifully Spartan Warehouse

4 minute read

For many new Facebook employees, their first days begin in front of a computer screen, learning the ins and outs of the company’s code. That code, after all, serves as the foundation of the company’s gigantic social network, hosting more than 1 billion daily visitors. With that in mind, it may be surprising to hear that Joel Kjellgren’s first six months at Facebook were spent working out of a construction trailer.

That’s because Kjellgren isn’t a traditional software engineer. He doesn’t work on the Like buttons, notification icons, or the other tools and buttons Facebook members push and poke on a regular basis. Rather, as the site manager of Facebook’s data center in Luleå, Sweden, Kjellgren’s oversees the massive facility that processes petabytes of data in the form of photos and stories posted to Facebook. It’s one of Facebook’s six such facilities that handle the hundred million hours of video watched and two billion photos shared through the social network every day.

“[It] was awesome to see how we turned something that was essentially just a concrete skeleton into one of the places [where] Facebook lives,” says Kjellgren of his early days working at the Swedish facility.

Joel KjellgrenFacebook

Facebook’s Luleå data center, located near the Arctic Circle, was the company’s first such facility outside the U.S. when it opened in 2013. Today, Facebook is offering a closer look inside the facility via the photos published above, which show the center itself as well as some of the people who run it.

The site is comprised of two colossal buildings, each about the size of 17 ice hockey rinks, full of gear that makes it possible for billions of people around the world to upload status updates, photos, and videos each day. As Facebook grows, so does the amount of hardware needed to store its users’ data. Since the Luleå facility opened in 2013, Facebook has built similar data centers in Ireland and Texas. It now plans to open one in New Mexico that will come online in late 2018.

Data centers on this scale require immense amounts of energy. Facebook says it’s working to make its facilities as clean as possible, aiming to use at least 50% renewable energy at all of them by 2018. The Luleå site is already powered entirely on clean energy, thanks in part to nearby hydroelectric dams that made the site attractive in the first place. The region’s arctic air also naturally cools the thousands of servers housed in the center; Facebook says its Luleå warehouses use almost 40% less power than traditional data facilities. (Facebook is far from being the only major technology company with such ambitions. Apple says its worldwide data centers run 100% on clean energy, while Google purchases green power from local wind and solar farms near its data facilities.)

But what gives Facebook a unique edge, Kjellgren says, is that it designs its data center hardware, then releases its work to other developers and engineers. This program, called the Open Compute Project, aims to do with data center hardware what open-source platforms like Linux have done for software. Gartner projects that data center systems’ spending will reach $174 billion in 2016.

“We come from a proud hacker background and from a company largely built upon open source philosophy in software,” Kjellgren says. “We just couldn’t understand why the same principles couldn’t apply to hardware.”

Finding efficient ways to manage the vast amounts of data that Facebook handles each day will only become more challenging as new types of media, like 360-degree video and virtual reality footage, rise in popularity. That means the technology used to store data shared to Facebook and operate its network will need to evolve as well. Accomplishing that at such a large scale is a daunting task; in the Luleå center alone, a job as seemingly trivial as routing cables is a full-time job.

“We stress test things that seem to [work] perfectly normal at a small scale,” Kjellgren says. “But once you get to a large scale, things might not work the way you expect . . . The types of problems we face, you usually can’t Google the solution for them.”

These enormous fans draw in the outside air to cool the servers in the data hall. In the winter, when temperatures plunge to -30 degrees the situation is reversed, and the heat from the servers warm the massive buildings.
These fans draw in air from the outside to cool the servers down. Conversely, when temperatures drop during the winter, heat from the servers warm the building.Facebook
The data center houses tens of thousands of servers.
The data center houses tens of thousands of servers. The data halls are frequently empty because only one technician is needed for every 25,000 servers, Facebook says. Facebook
Director of data center design engineering, Jay Park.
Jay Park, director of data center design and engineeringFacebook
Late one night, while traveling, Jay sketched his vision for the center on this napkin.
Park sketched his original idea for the data center's design on the back of a napkin.Facebook
Each technician services about 25,000 servers. Emilie De Clercq, Data Center Technician.
Emilie De Clercq, data center technician.Facebook
he equipment is reduced to its basics so it runs cooler. It can also be easily accessed and repaired quickly. A few years ago, it took an hour to repair a server hard drive, now it's down to two minutes.
It takes just two minutes to repair a server hard drive at Facebook's data centers, compared to a few years ago when it took an hour, according to the company. Facebook
Old and obsolete hard drives are crunched to protect privacy. Christer Jonsson is in charge of this.
Christer Jonsson is in charge of crushing old and obsolete hard drives, a measure Facebook takes to protect privacy.Facebook
Crushed hard drives.
Here's what the hard drives look like after being crushed.Facebook
The center opened in 2013, and was Facebook's first outside the US.
The center opened in 2013, and was Facebook's first outside the US.Facebook
Luleå is a small coastal town just south of the Arctic Circle, and near the top of the world.
Luleå, just south of the Arctic Circle and near the top of the world, was an appealing location for a data center thanks to its cool climate and renewable energy sources.Facebook

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