

The Erlang Distribution - coglethorpe
http://en.wikipedia.org/wiki/Erlang_distribution

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pietro
I wonder if anyone ever used Erlang distributions for website performance
metrics.

His math should apply and offers an effective, statistically valid method of
estimating resource requirements, much superior to the usual "requests per
second".

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strlen
Actually this is explicitly applicable to the web/Internet performance. The
person who discovered this distribution was the same person for whom the
language Erlang is named after-- and was developed for the purpose of
predicting waiting times between telephone calls. This also describes times of
web page requests arriving to a server.

Much of what flowed out (queuing theory) can just as well be applied to
Internet packets or to web servers (with various threading/request handling
models corresponding to various queues) processing requests.

This may not sound exciting, but it's vitally important (particularly for
modeling and simulation-- which is vital in cases where you can't do a live
test of a certain algorithm without incurring an expense).

Fundamentally these algorithms are fairly easy to implement: all you need is a
prng producing the specific distribution. I wonder how many of the HTTP stress
tools actually do this, though.

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rms
Wow, this is so boring I flagged it.

This is the distribution you use to analyze people waiting in lines! Unless it
doesn't fit right in which case you just use another distribution.

