[ntp:questions] Any chance of getting bugs 2164 and 1577 moving?

unruh unruh at invalid.ca
Thu Mar 22 18:00:58 UTC 2012


On 2012-03-22, David J Taylor <david-taylor at blueyonder.co.uk.invalid> wrote:
> "unruh" <unruh at invalid.ca> wrote in message 
> news:xLHar.38386$IQ1.34248 at newsfe18.iad...

> []
>> Measure what? Why do you think that ntp reporting the offset with an
>> extra three decimal points would allow you to measure anything? What in
>> your mind would you expect to see in that output that would allow you to
>> "measure" something that would tell you that the -19 was wrong? Remember
>> ntpd DID measure something in order to determine that -19. What do you
>> think the extra decimal places would give you?
>
> Most likely I would be looking at a histogram of the reported offsets, and 
> see whether it was gaussian, flat, or whatever, and how wide.  I might 
> learn something from that.

No. Not if it is just noise. 

>
> Others have reported precisions better than -19, and also have a need for 
> greater reporting precision.

That is a valid issue. 

>
> There seems to be an impression out there that I'm trying to show 
> something is wrong - I'm not.  I suggested an enhancement so that the 
> precision of ntpq matched that of the loopstats.  That's all.

precision is not accuracy.
In science we teach students not to report unwarranted precision-- the
precision should reflect the accuracy of the measurements. We keep
getting measurements to the mm and reported precision to angstoms
because that was what the calculator spit out. 
 I am not averse to reporting with a precion maybe up to a factor of 10
better than the accuracy, but any more is just silly and misleading (as
you are demonstrating in believing that a greater precision would convey
some extra information. 

>
> David 
>



More information about the questions mailing list