Google Running About 900,000 Servers | Hacker News Reader

Google Running About 900,000 Servers

datacenterknowledge.com

34 points1SockChuck8 comments

Maybe I'm missing some of the math, but the only number this whole article seems to be based on is hearsay Google power usage of "less than 1% of 198.8 billion kWh" Somehow this number gets extrapolated to "Google may be running its entire global data center network in an energy footprint of roughly 220 megawatts of power." Which then means "the company is probably running about 900,000 servers" against previous "guesstimates have placed Google’s server count at more than 1 million."

My goodness, a 10% difference from the old guesstimates on stats like "less than 1%"? This article didn't do much for me.

Google's estimated power usage is not hearsay in this case, from the actual article (linked to):

"To my knowledge, this is the first time that Google has revealed specific details about their total data center electricity use (they gave me an upper bound, not an exact number"

In doing the electricity --> server guess, he gave them up to a 30% credit for self-assembled vs. off the shelf servers.

Agreed. It's just content filler, of no worth whatsoever.

Question: each 'server' is made up of cheap commodity hardware - but is the storage side of things handled elsewhere? YouTube alone takes 2 days worth of new video every minute - and stores multiple bitrate versions and the source video. That alone, for example, would cause problem for 900,000 commodity-sized hard disks...

Google's storage is built on servers. http://labs.google.com/papers/gfs.html

You can easily put 6 disks in a server, and they may have some specialized designs that hold more.

Google has moved past GFS, but the basic concept is right: every machine in the cluster is a storage server.

There are some machines that are equipped with more disks than others where local density is needed.

As a ballpark estimate 2 days worth of video in multiple formatats is around 24 blue ray disks @ 25 gigabytes per disk or 600 gigabytes per minute. (Note: most of their video is not HD yet so this is a fairly high estimate.) That means a 2TB disk lasts around 3.3 minutes and they need around 150,000 disks per year. Which including redundancy is in the right ballpark for 900,000 disks. But, they could easily have 6+ disks per server.

But you can easily handel that much bandwidth on 5% of those disks so aslong as your not trying to fill up one disk at a time it's really not an issue.

tl;dr: a totally speculative number.

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