I've just started getting interested in precision timekeeping - if you can call an offset from UTC that is measured in units of milliseconds "precision".
My current timeserver is a Buffalo Linkstation, patched to run Debian Stable, and slaved via 2MBit ADSL to my ISPs Stratum 2 timeserver, using NTP V4.2.0, from the Debian Stable repository. I'm seeing offsets in the low millisecond range, but with frequent excursions up to 10 to 20 millisec or more. These large spikes in the offset curve are definitely correlated with large data transfers down from the Internet. Look at http://www.g8kbz.demon.co.uk/mrtg.html for a sample plot, derived by MRTG, and updated daily at midnight local time. There seems to be no prospect of mitigating these offset spikes without taking further steps, and I intend to install a new timeserver, probably using a Soekris NET4801 and a Garmin GPS18LVC. I hope to effect a 3 order of magnitude improvement in observed offset, and more would be appreciated - I've already been bitten by the precision bug. So my question is - should I continue with Debian Stable, or would OpenBSD be better for sub-microsecond accuracy? Indeed, is sub- microsecond offset achievable with this hardware? GPSDOs and Rb or Cs standards are not yet practical politics. Thanks in advance for any tips, -- Geoff Powell _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
