[ntp:questions] different request pattern
David Woolley
david at ex.djwhome.demon.co.uk.invalid
Tue Jul 1 07:10:19 UTC 2008
arne_woerner at yahoo.com wrote:
> 2. "offset per second" describes the estimated offset-difference after
> a second...
> i compute it like this (dont laugh :-) ):
> (adjtime_offsets + estimated_offset_to_server_X)/T
> let T be the time when the offset to server X was 0
> let adjtime_offsets be the sum of the adjtime() offsets in the last T
> seconds...
That seems to me to be an estimate of the local machine's clock
frequency, evaluated over an excessively short period in relation to
network timing jitter. 10ms/s would be 10,000 parts per million, which
is much much higher than you would get even from a real false ticker,
and could only really represent the result of jitter. On a heavily
loaded connection, traffic variations can results in offsets varying by
hundreds of milliseconds (relative to true time).
More information about the questions
mailing list