[ntp:questions] Time slew doesn't seem to work

Unruh unruh-spam at physics.ubc.ca
Fri Apr 11 00:41:14 UTC 2008

David Woolley <david at ex.djwhome.demon.co.uk.invalid> writes:

>Unruh wrote:
>> Not at 500PPM limit but if you use the tick adjustment, it is more than
>> enough time. (The tick adjust limits out at 100,000PPM)
>I believe ntpd assumes that it is constant.  Having a large tickadj 
>causes poor resolution when using the user space discipline.

Yes, ntpd does limit all slews to 500PPM (the limit on the freq adjust
parameter in adjtimex on linux as well). I was just saying that a slew of 2
sec in 15min IS possible, although ntpd will not do it. 

>I suspect that Dr Mills would say that a high slew rate also compromises 
>the system behaviour when you cascasde multiple strata.

Not sure why, but maybe. 

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