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

unruh unruh at invalid.ca
Wed Mar 21 19:55:53 UTC 2012


On 2012-03-21, David J Taylor <david-taylor at blueyonder.co.uk.invalid> wrote:
> "unruh" <unruh at invalid.ca> wrote in message 
> news:itmar.5841$yD7.508 at newsfe15.iad...
> []
>> But -19 is about 2 microseconds if I understand it correctly. That means
>> that the clocks are incapable of delivering more than about 2
>> microseconds of accuracy. What is you  that last decimal digit of
>> accuracy in the offset is thus pure noise-- dominated by clock reading
>> noise. Why is it important for you then?
>
> When I can see the decimal places, then I will know whether the precision 
> estimate is reasonable.  Just getting values such as -1, 0, 1 microseconds 
> is insufficient to make that call.

And how will the extra decimals help? The -19 was determined by making
successive calls to the clock and seeing how much it changed between
successive readings. That gives a good estimate of how long it takes to
make a call to the clock. Any precision in the answer beyond that is not
accuracy. I could give you the time to 60000 decimal places, each one of
the diffetent, but the last 5995 just being garbage (random numbers)
Would that tell yo uanything? 
If for some reason you do not believe ntpd's estimation of your clock
accuracy, develope a better algorithm for determining it. It is a bug is
ntpd is reporting an accuracy much worse than it actually is. 

Ie, you have no data to make that call even if you get more digits. 


>
> David 
>



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