[ntp:questions] NTP on CubieBoard

William Unruh unruh at invalid.ca
Mon Oct 13 16:28:20 UTC 2014


On 2014-10-13, David Woolley <david at ex.djwhome.demon.invalid> wrote:
> On 13/10/14 09:23, Rob wrote:
>> On the PC platform, with a recent development ntpd I can achieve
>> PPS sync with offset within a couple of us on systems in normal
>> environment, and well within 1us in a temperature conditioned room.
>
> The correct quality measure is jitter, rather than offset.  offset 
> varies from sample to sample but still doesn't tell you the systematic 
> error in the time.

Not sure you meant to say that as nothing tells you the systematic error
in time. If something did, ntpd would use it to get rid of that
systematic error. But also, offset is the only measure you have of the
error, and is what ntpd uses to control the clock. Or did you mean
something else?

>



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