Under the Hood: The entities graph (Eric Sun is a tech lead on the entities team, and Venky Iyer is an engineering manager on the entities team.)
From the post:
Facebook’s social graph now comprises over 1 billion monthly active users, 600 million of whom log in every day. What unites each of these people is their social connections, and one way we map them is by traversing the graph of their friendships.
But this is only a small portion of the connections on Facebook. People don’t just have connections to other people—they may use Facebook to check in to restaurants and other points of interest, they might show their favorite books and movies on their timeline, and they may also list their high school, college, and workplace. These 100+ billion connections form the entity graph.
There are even connections between entities themselves: a book has an author, a song has an artist, and movies have actors. All of these are represented by different kinds of edges in the graph, and the entities engineering team at Facebook is charged with building, cleaning, and understanding this graph.
Instructive read on building an entity graph.
Differs from NSA data churning in several important ways:
- The participants want their data to be found with like data. Participants generally have no motive to lie or hide.
- The participants seek out similar users and data.
- The participants correct bad data for the benefit of others.
None of those characteristics can be attributed to the victims of NSA data collection efforts.