Bad math again?

I wonder who’s really, really bad at math: me or George Gilder and the Wired editors:

“To handle the current load of 100 million queries a day, its collective input-output bandwidth must be in the neighborhood of 3 petabits per second.”

(From page 2 of a Wired story).

I’m willing to concede that there are things I don’t know about Google and/or Gilder’s calculation (not to mention his penchant for big numbers), but according to my calculation, that’s off by a factor of about 20 million. What a big number _that_ is! I’m impressed! I can’t think of any junk I could add to my calculation to get anywhere near that.

For your reference, since you care enough to read to the end of this article, my calculation was thus: I did a Google query and added the 5kB page to the two 5kB images (which are usually cached for me, but we’ll assume they never are) plus 1kB up for the request, to get 16kB per query.

16kB * 8b/B * 100e6/day / 24hr/day / 3600s/hr = 148Mb/s

3e15b/s / 148Mb/s = 20e6

One comment

  • 2006/10/15 - 06:33 | Permalink

    You forgot that that Google has to send the same data, in triplicate, to the NSA.
    But even with that, it’s still off by a hell of a lot.

    Or he is talking about Imperial petabits intead of metric petabits.

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