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Re: How do you (not how do I) calculate 95th percentile?

  • From: Warren Kumari
  • Date: Wed Feb 22 14:29:41 2006 
On Feb 22, 2006, at 10:12 AM, Jo Rhett wrote:

A lot of smaller folks check the counter every 5 min and use that same
value for the 95th percentile. Most of us larger folks need to check more
often to prevent 32bit counters from rolling over too often. Are you larger
folks averaging the retrieved values over a larger period? Using the
maximum within a larger period? Or just using your saved values?
Most people are using 64 bit counters. This avoids the wrapping problem (assuming you don't have 100GE and poll more then once every 5 years :-)).

This is curiosity only. A few years ago we compared the same data and the
answers varied wildly. It would appear from my latest check that it is
becoming more standardized on 5-minute averages, so I'm asking here on Nanog
as a reality check.
Yup, 5 min seems to be the accepted time.

Note: I have AboveNet, Savvis, Verio, etc calculations.  I'm wondering
if there are any other odd combinations out there.

Reply to me offlist.  If there is interest I'll summarize the results
without identifying the source.

--
Jo Rhett
senior geek
SVcolo : Silicon Valley Colocation