From CNET,

Stephen Shankland writes about Google’s Datacenter Infrastructure and what runs the search/advertisement giant. You have to read it for yourself! Its pretty amazing to finally read about Google and how they operate on the backend.

Here are some quotes,

Google doesn’t reveal exactly how many servers it has, but I’d estimate it’s easily in the hundreds of thousands. It puts 40 servers in each rack, Dean said, and by one reckoning, Google has 36 data centers across the globe. With 150 racks per data center, that would mean Google has more than 200,000 servers, and I’d guess it’s far beyond that and growing every day.

In each cluster’s first year, it’s typical that 1,000 individual machine failures will occur; thousands of hard drive failures will occur; one power distribution unit will fail, bringing down 500 to 1,000 machines for about 6 hours; 20 racks will fail, each time causing 40 to 80 machines to vanish from the network; 5 racks will “go wonky,” with half their network packets missing in action; and the cluster will have to be rewired once, affecting 5 percent of the machines at any given moment over a 2-day span, Dean said. And there’s about a 50 percent chance that the cluster will overheat, taking down most of the servers in less than 5 minutes and taking 1 to 2 days to recover.

The MapReduce reliability was severely tested once during a maintenance operation on one cluster with 1,800 servers. Workers unplugged groups of 80 machines at a time, during which the other 1,720 machines would pick up the slack. “It ran a little slowly, but it all completed,” Dean said.

And in a 2004 presentation, Dean said, one system withstood a failure of 1,600 servers in a 1,800-unit cluster.

Well, if that isn’t amazing, I don’t know what is.