by Phil Wong, The Rumpus
This past summer Facebook relocated from University Avenue in Palo Alto, CA -- where several buildings fan out along the downtown strip -- to a new central office in Stanford Research Park. A good friend and two-year veteran of Facebook invited me to check out the new space. When I arrived, a security guard handed me a non-disclosure contract to fill out, a requirement to enter the building. "Just making sure you're not a .Twitter spy," he said. I can therefore not describe the tour my friend gave, though photos of the new space abound on the Internet. Afterwards, we went out for a drink at the Dutch Goose, a bar popular with techies and Stanford graduate students, where most of this conversation took place. Though forthcoming, my friend was anxious to preserve her anonymity; Facebook employees, after all, know better than most the value of privacy. As she is not permitted to divulge company secrets, and would like to remain employed, her name has been omitted from this interview. It provides an interesting snapshot of the inner workings and culture of Facebook in the summer of 2009.
The Rumpus: On your servers, do you save everything ever entered into Facebook at any time, whether or not it's been deleted, untagged, and so forth?
Facebook Employee: That is essentially correct at this moment. The only reason we're changing that is for performance reasons. When you make any sort of interaction on Facebook -- upload a photo, click on somebody's profile, update your status, change your profile information --
Rumpus: When you say "click on somebody's profile," you mean you save our viewing history?
Employee: That's right. How do you think we know who your best friends are? But that's public knowledge; we've explicitly stated that we record that. If you look in your type-ahead search, and you press "A," or just one letter, a list of your best friends shows up. It's no longer organized alphabetically, but by the person you interact with most, your "best friends," or at least those whom we have concluded you are best friends with.
Rumpus: In other words, the person you stalk the most.
Employee: No, it's more than just that. It's also messages, file posts, photos you're tagged in with them, as well as your viewing of their profile and all of that. Essentially, we judge how good of a friend they are to you.
Rumpus: When did Facebook make this change?
Employee: That was actually fairly recently, sometime in the last three months. But other than that, we definitely store snapshots, which is basically a picture of all the data on all of our servers. I want to say we do that every hour, of every day of every week of every month.
Rumpus: So this is every viewable screen?
Employee: It's way more than that: it's every viewable screen, with all the data behind every screen. So when we store your photos, we have six versions of your photos. We don't store the original: we make six different versions on the photo uploader and upload those six versions.
Rumpus: And the difference between them would be sizing, certain areas are zoomed --
Employee: Exactly. Different sizes for the news feed, your profile pic, enlargement.
Rumpus: And these reside on servers in your office?
Employee: No, not in our office. Absolutely not. We have four data centers around the world. There's one in Santa Clara, one in San Francisco, one in New York and one in London. And in each of those, there are approximately five to eight thousand servers. Each co-location of our servers has essentially the same data on it.
Rumpus: And how many users are you up to now?
Employee: That I can disclose publicly? Two hundred to two hundred twenty million.
Rumpus: And actually?
Employee: That's just active users. As far as total accounts, including those that are potentially fake, disabled and whatnot, we're over three hundred million. The two hundred twenty million are users who have logged on and done something with the site in the last thirty days.
Rumpus: You said they're changing the policy of keeping all information.
Employee: No. They're never changing that policy. We still keep all information. What I was referring to, is that if anything, we're going to start deleting more photos for performance reasons. We are the largest photo distributor in the world.
Rumpus: Really? Is that obvious?
Employee: I don't know the exact figures off the top of my head, but I want to say upwards of a trillion photos, and then think about six copies of each. This is the epitome of a needle in a haystack. When we need to load a webpage in half a second, we need to go and find upwards of a thousand photos -- think about your newsfeed -- in one get [snaps], and instantaneously. It's hard to do.
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