[ntp:questions] Peer Review of ntpq -c rv

David J Taylor david-taylor at blueyonder.co.uk.invalid
Wed Mar 7 14:50:59 UTC 2012

"Alby VA" <albyva at empire.org> wrote in message 
news:d2d5cf76-b61e-4e58-800b-a1c27a63dc92 at hs8g2000vbb.googlegroups.com...
> I'm looking to get a little feedback on if the following output of my
> Sure GPS / FreeBSD
> setup looks like its running smoothly and keeping time correctly.
> assID=0 status=0115 leap_none, sync_atomic, 1 event,
> event_clock_reset,
> version="ntpd 4.2.6p5 at 1.2349-o Mon Feb 20 22:00:33 UTC 2012 (1)",
> processor="amd64", system="FreeBSD/9.0-RELEASE", leap=00, stratum=1,
> precision=-19, rootdelay=0.000, rootdisp=0.269, refid=PPS,
> reftime=d301d22f.dc1393c2  Wed, Mar  7 2012  7:25:19.859,
> clock=d301d230.cc08bad9  Wed, Mar  7 2012  7:25:20.797, peer=41909,
> tc=4, mintc=3, offset=-0.034, frequency=-25.214, sys_jitter=0.002,
> clk_jitter=0.002, clk_wander=0.001
> Here are my website graphs/stats I've been keeping since day 1.
> NTP Clock Offset: http://godzilla.empire.org:9999/
> NTP Offset from UTC: http://godzilla.empire.org:9999/godzilla_ntp-b.html

For comparison, a GPS 18 LVC feeding a FreeBSD 8.2 system, which is /only/ 
doing NTP service:


Offsets in the few microseconds region, whereas yours are at the 
millisecond level, which seems to be a large factor out.  Any chance your 
"NTP Clock Offset" graph is mislabeled?  In case it's any help:

associd=0 status=0419 leap_none, sync_uhf_radio, 1 event, leap_armed,
version="ntpd 4.2.7p255 at 1.2483 Fri Feb 10 06:04:36 UTC 2012 (1)",
processor="i386", system="FreeBSD/8.2-RELEASE-p6", leap=00, stratum=1,
precision=-19, rootdelay=0.000, rootdisp=1.060, refid=PPS,
reftime=d301f2ab.e61f80cb  Wed, Mar  7 2012 14:43:55.898,
clock=d301f2b0.389c6063  Wed, Mar  7 2012 14:44:00.221, peer=8406, tc=4,
mintc=3, offset=0.000, frequency=28.159, sys_jitter=0.002,
clk_jitter=0.002, clk_wander=0.002, tai=34, leapsec=201207010000,

For comparison, my Windows PCs connected to Sure boxes are PCs Feenix and 
Alta, and I would expect them to be rather worse than Free BSD.  Graphs 


(Before anyone asks, PCs Stamsund and Bacchus are connected to GPS 18x and 
GPS 18 LVCs, and Bacchus does a disk defrag every Wednesday morning which 
takes 100% of the CPU, and rather disturbs the timekeeping!)


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