Google now employs 800 people, yet it handles 200 million searches of the Web each day, a staggering one-third of the estimated daily total. To keep up with that torrent, Google has essentially built a home-brew supercomputer that is distributed across eight data centers.
The company stopped giving updates on the size of its computing resources in 2001. But several people with knowledge of the system said it consists of more than 54,000 servers designed by Google engineers from basic components. It contains about 100,000 processors and 261,000 disks, these people said, making it what many consider the largest computing system in the world.