Yo All!

I have some solid results on minpoll=maxpoll=1.  That gives a
poll time of 2 seconds.  When minpoll=maxpoll=0 works Ill be testing
that.  UNtil thne I'll be testing other values.

First, the good news.  On a Raspberry Pi 3B, with Uputronics hat, 
minpoll=maxpoll=1 is much better than minpoll=maxpoll=6 (64s).

At poll=64:

      Local Clock Freq Offset: 90% 1.4ppm, Jitter 90% 3.3 us
      Local Stability 90%: 2.2 ppt
      PPS Offset  90% 68us, Jitter 90% 9.7 us

At poll=2:

      Local Clock Freq Offset: 90% 1.1ppm, Jitter 90% 0.43 us
      Local Stability 90%: 2.3 ppt
      PPS Offset  90% 1.6us, Jitter 90% 0.34 us


See attached pi3-local-offset.png.  Before 18:25 12 Sep 2016 UTC is poll=64s
after is poll=2.  Pretty nice, a very good improvement in time, for a slight
decrease in frequency.  And NTP is all about time, right?

Now the bad news.  On a quad XEON, with an MR-350P serial GPS:

At poll=64
    Local Clock Freq Offset: 90% 570ppb, Jitter 90% 10.2 us
    Local Stability 90%: 1.2 ppt
    PPS Offset  90% 34.2us, Jitter 90% 16.3 us

At poll=2

    Local Clock Freq Offset: 90% 495ppb, Jitter 90% 16.9 us
    Local Stability 90%: 27.7 ppt
    PPS Offset  90% 39.0us, Jitter 90% 26.7 us

See attached spidey-local-offset.png.  Before 18:10 12 Sep 2016 UTC is poll=64s
after is poll=2.  That went really, really badly...

So, the answer to the best poll?  It depends...

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        g...@rellim.com  Tel:+1 541 382 8588

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