"Richard B. Gilbert" <[email protected]> writes: > unruh wrote: >> On 2010-05-02, Richard B. Gilbert <[email protected]> wrote: >>> Wolfgang Breyha wrote: >>>> Hi! >>>> >>>> I'm running a soekris net4801 with openwrt 10.03. kernel 2.6.32.10 with >>>> LinuxPPS patch and ntpd 4.2.6p1. >>>> >>>> Today I recognized that my /dev/ttyS1 gets a input buffer as soon as I run >>>> ldattach PPS /dev/ttyS1 >>>> >>>> The buffer is hold until somebody connects to /dev/ttyS1 and reads it. This >>>> is reproduceable with "cat" at any time. >>>> >>>> ntpd gets confused by the input at start big time and needs really long to >>>> settle. >>>> >>>> I have not found the cause of this yet. Has somebody noticed similar >>>> behaviour? >>>> >>>> Greetings, Wolfgang >>> NTPD has always needed a long time to settle. From a cold start >>> you need to wait ten to twelve hours for the time to reach the best >>> possible accuracy! This is not a great problem if you keep NTPD >>> running 24x7. >> >> Actually it is a problem for the best clock discipline, because it >> means that ntp also reacts very slowly to >> changes like temperature chages. >> > > If temperature changes and the clock's reaction to them are a problem, > there are many things that can be done to create an environment that > will maintain a closely controlled temperature.
Or alternately if the temperature reading were available to ntp, it could maintain a separate drift value for each temperature. -wolfgang -- Wolfgang S. Rupprecht If the airwaves belong to the public why does the public only get 3 non-overlapping WIFI channels? _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
