Behind the Scenes of a Google QueryJuly 8, 2008 – 6:02 AM
A lot of people have used Google but few have any idea as to the complexity and computer power necessary to return billions of queries with millions of results all in under a second. This isn’t by accident, an oversight by Google or even due to security concerns, Google believes in not making search seem complicated to users. This notion is perhaps best illustrated in Google’s “Technology Overview”, which uses just 5 images and 4 sentences to explain the “Life of a Google Query”.
Despite Google’s simplistic interface, search is complicated. For example when a user in San Francisco enters a query like google.com/search?q=blogoscoped, the user’s browser first completes a DNS lookup mapping www.google.com to a specific IP address. At this stage, Google’s DNS load balancer determines which cluster of computers at which of Google’s 36+ data centers will process the query.