[ntp:questions] Re: Best way to harness multiple stratum 1 servers
Richard B. Gilbert
rgilbert88 at comcast.net
Thu Apr 6 18:48:23 UTC 2006
Terje Mathisen wrote:
> Richard B. Gilbert wrote:
>> I believe I have read the PHK has modified the ntpd PLL for use with
>> refclocks such as GPS and Cesium. I don't know PLL design from a hole
>> in the ground but he might have improved the design for that specific
>> purpose. It's worth looking into!!
>> BTW, what hardware and O/S are you using for this project? Solaris
>> 8/SPARC keeps time to a precision of one microsecond. I don't know of
>> any hardware/software that supports a higher precision but there may
>> well be some.
> AFAIK, Sun was the first to implement nanosecond kernel time resolution,
> it is definitely a standard part of all FreeBSD systems, and an absolute
> requirement if you want sub-microsecond GPS/Cs performance.
> Ulrich Windl have maintained a set of patches to Linux to get ns there
> as well.
Where does Solaris keep the nanoseconds?
The precision shows as "-21" or about 1 microsecond and, indeed, the
smallest difference between two consecutive calls to gettimeofday() is
Is there some documented and supported way to access the nanosecond part
of the time?
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