With construction on its new Oregon data center only recently underway, Facebook has decided to double the size of the facility to handle current demand from its 500 million users and offer headroom for the additional growth the company anticipates in the future, says Data Center Knowledge.Originally planned to encompass 147,000 square feet, the Prineville, Oregon facility-still in the very early stages of construction-will now be expanded to 307,000 feet, the company said.

From a news article on datacenterknowledge.com:

Facebook's decision to commit to an expansion before it has even completed the first phase of the facility reflects the accelerated pace of pace of infrastructure growth for the social network, which recently reached 500 million active users.

"We are making excellent progress on the first phase of our Prineville Data Center and we are hoping to finish construction of that phase in the first quarter of 2011," said Tom Furlong, Director of Site Operations for Facebook. "To meet the needs of our growing business, we have decided to go ahead with the second phase of the project, which was an option we put in place when we broke ground earlier this year. The second phase should be finished by early 2012."

For the growing number of people who need to know more about the high-velocity, high-volume data centers that are powering our technology-rich global economy, Rich Miller, the brains behind DataCenterKnowledge.com, has compiled a nice set of resources at the bottom of his article about the newly expanded Facebook facility.

In one of those articles, published about five weeks ago, Miller says, "Facebook now is using 60,000 or more servers to support its fast-growing service, according to an analysis of data from company presentations last week. The social network's infrastructure performs more than 50 million operations per second."