
Estimating Google's number of servers using the WWII tank method - nickb
http://www.daltonlp.com/view/507
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ed
The German tank method relies on a unique probability density function created
specifically for the task of estimating tank production.

It takes into account factors unique to tanks, so you'd have to define your
own distribution for Goolge's gadget servers to make a correct estimation.

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daltonlp
Factors unique to tanks? I thought it assumed only that tanks would be
assigned unique sequential ID numbers.

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daltonlp
Someone else pointed out the most likely accuracy issue - Google may (probably
does) use a dynamic balancing system to add and remove servers/nodes according
to load.

The checks I ran were done over just 4 days. The resulting numbers may have no
relevancy at all over other time periods with different load amounts.

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cstejerean
I don't know much about the German tank method but it seems interesting that
given 62 unique addresses with a maximum of 103 it would give a total number
of 104. This doesn't seem to make sense to me. Can someone explain why this
works this way?

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darius
You need to read the explanation for the German Tank method
(<http://www.guardian.co.uk/g2/story/0,,1824525,00.html>) to see the formula
used to get 104.

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patrickg-zill
well there are 42U in a rack, does that help?

