Of the more than 150 million active Facebook users, about 13 million users update their statuses at least once each day, which results in almost 3 billion minutes spent on Facebook daily.
This much network traffic has made Facebook No. 5 in top global Web sites, behind leaders Yahoo, Google, YouTube and Windows Live, respectively, according to Alexa, a Web information company that tracks and reports traffic rankings. According to comScore, Facebook is the leading social networking site based on monthly unique visitors, having overtaken main competitor MySpace in April 2008.
Facebook’s power derives from what vice president of technology Jeff Rothschild calls the “social graph” – the sum of the wildly various connections between the site’s users and their friends; between people and events; between events and photos; between photos and people; and between a huge number of discrete objects linked by metadata describing them and their connections.
Rothchild, an alumnus of Vanderbilt’s School of Engineering, will kick off a spring lecture series sponsored by the department of electrical engineering and computer science, at 3 p.m., Thursday, Jan. 29, in Featheringill Hall’s Jacobs Believed in Me Auditorium.
The lecture is open to the public. However, this is a lecture about technology, not a discussion of online social networking. Rothschild will focus on how the company’s technology manages a rapidly expanding web of connections for its millions of users.
At Facebook, Rothschild focuses on scalability and performance.
Facebook maintains data centers in Santa Clara, CA; San Francisco; and Northern Virginia. The centers are built on the backs of three tiers of x86 servers loaded up with open-source software, some that Facebook has created itself, Technology Review reported in its August edition.
Facebook has built a lightweight but powerful multi-language RPC framework that allows the company to seamlessly and easily tie together subsystems written in any language, running on any platform. The company is the largest user in the world of memcached, an open-source caching system, and has created a custom-built search engine serving millions of queries a day, completely distributed and entirely in-memory, with real-time updates.
What’s next for Facebook’s technology? Rothschild told Technology Review the company has discovered that interrupts on the servers’ Ethernet controllers – which let the servers process myriad requests arriving at the same time – are a bottleneck. So Facebook rewrote the controllers’ drivers to scale on multicore systems. Facebook is also experimenting with solid-state drives, which could speed the performance of the MySQL database tier by a factor of 100.
Prior to Facebook, Jeff focused on storage management and Internet services as an investor and entrepreneur. Rothschild co-founded VERITAS and helped establish the company as the leader in storage management software.
He also co-founded Mpath Interactive/Hearme, the Internet multiplayer games and voice chat service, where he served as vice president of engineering. He is also a consulting partner with Accel Partners and during his tenure has worked with Walmart.com, Rhapsody Networks and Mendocino Software.