> [email protected] said: > remote refid st t when poll reach delay offset jitter > ============================================================================== > x127.127.28.0 .NMEA. 0 l 3 16 377 0.000 -994.05 7.857 > x127.127.28.1 .PPS. 0 l 7 16 377 0.000 -250.13 572.812 > +192.168.64.18 .PPS. 1 u 66 128 377 0.553 -0.055 0.033 > *192.168.64.2 .PPS. 1 u 99 128 377 0.237 -0.062 0.039 > +192.168.64.168 .PPS. 1 u 44 128 377 0.646 -0.013 0.321 > > Something is broken. What NMEA device are you using? Why are you using gpsd
It is a garmin 18x lvc. > rather than ntpd's NMEA driver? Oh for convenience. I need to patch ntpd to use linux pps (afaik) and on other systems I successfully run gpsd with ntpd (read: low jitter). > It looks like the NMEA side it is off by a second. Some devices do that. > You can fix that with some fudging. Yes, I'm not so worried about the nmea part, I might even decide to remove it from the configuration. What I mean is: if I set the clock to the current time, than it is only a matter of keeping it at that with the pps. > The PPS stuff is off by 250 ms. Are you using the wrong edge? (Got a scope > handy?) Well, the offset is not constant. If you look at http://keetweej.vanheusden.com/~folkert/nanosg20.png you see it is between 0 and -1ms. I now notice that it is not random-ish but consists of a few specific values: folkert@belle:~$ cat peerstats | grep 127.127.28.1 | awk '{ print $5; }' | cut -c 1-6 | sort | uniq -c | sort -rn 503 -0.874 497 -0.875 486 -0.999 467 -1.000 365 -0.249 332 -0.250 201 -0.857 188 -0.125 184 -0.142 140 -0.124 131 -0.000 113 0.0000 108 -0.166 24 -0.833 5 -0.200 2 -0.856 2 -0.799 2 -0.199 1 -0.167 1 -0.143 1 0.0002 1 0.0001 This is with 3754 lines. If I clean it a little: 1000x -0.8745 953x -0.9995 697x -0.2495 328x -0.1245 and so on. Folkert van Heusden -- MultiTail är ett flexibel redskap för att följa en eller flera logfiler, utföra kommandon, filtrera, färglägga, sammanfoga, o.s.v... ---------------------------------------------------------------------- Phone: +31-6-41278122, PGP-key: 1F28D8AE, www.vanheusden.com _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
