[ntp:questions] making sense of stats offset values [or trying to...]
David J Taylor
david-taylor at blueyonder.not-this-part.nor-this.co.uk.invalid
Tue Apr 28 07:23:45 UTC 2009
David Woolley wrote:
> David J Taylor wrote:
>> David Woolley wrote:
>>> Bruce Lilly wrote:
>>>> # ntpq -p
>>>> remote refid st t when poll reach delay
>>>> offset jitter
>>>> *megatron.blilly 220.127.116.11 2 u 27 64 377
>>>> 2.927 0.296 0.122
>>>> # ntptrace
>>>> megatron.blilly.net: stratum 2, offset 0.002120, synch
>>>> distance 0.024161
>>>> Note that ntpq reports an offset of 0.296 milliseconds from
>>>> the local host to its system peer, while
>>>> ntptrace reports an order of magnitude larger offset!
>>> 2.120 milli-seconds is not an order of magnitude different. I think
>>> you are expecting milliseconds to have three zeros after the
>>> decimal point; they don't!
>> I'm missing something here - how are 0.296ms and 2.120ms not about
>> "an order of magnitude different"?
> My mistake. I looked at the decimal point on the delay; it wrapped to
> the start of the line.
> However, as noted, that is the difference between a one shot
> measurement and a filtered one.
Thanks, David. I found your explanations most helpful, so thanks for
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