/contrib/ntp/scripts/stats/README.stats

  1Statistics file formats (README.stats)
  2
  3The xntp3 daemon can produce a variety of statistics files which are
  4useful for maintenance, evaluation and retrospective calibration
  5purposes. See the xntpd.8 man page for instructions on how to configure
  6this feature. Since these files can become rather large and cumbersome,
  7they are ordinarily reduced to summary form by running the summary.sh
  8shell script once per day, week or month, as appropriate. There are
  9three file collections presently defined: peerstats, loopstats and
 10clockstats, each of which is described in this note.
 11
 12peerstats
 13
 14The following data are collected in the peerstats files. The files are
 15reduced to summary data using the peer.sh shell script. See the peer.awk
 16script for further information. A line in the file is produced upon
 17reception of each valid update from a configured peer.
 18
 19  49236 30.756 140.173.96.1 9474 0.000603 0.37532
 20
 21  49236             modified Julian day number
 22  30.756            time of day (s) past midnight UTC
 23  140.173.96.1      peer identifier (IP address or receiver identifier)
 24  9474              peer status word (hex) (see NTP specification)
 25  0.000603          offset (s)
 26  0.08929           delay (s)
 27  0.37532           dispersion (s)
 28
 29loopstats
 30
 31The following data are collected in the loopstats files. The files are
 32reduced to summary data using the loop.sh shell script. See the loop.awk
 33script for further information. A line in the file is produced at each
 34valid update of the local clock.
 35
 36  49236 11.897 -0.000004 -35.9384 0
 37
 38  49236             modified Julian day number
 39  11.897            time of day (s) past midnight UTC
 40  -0.000004         time offset (s)
 41  -35.9384          frequency offset (ppm)
 42  0                 phase-lock loop time constant
 43
 44clockstats
 45
 46The following data are collected in the clockstats files. The files are
 47reduced to summary data using the clock.sh shell script, which also
 48updates the ensemble, etf, itf and tdata data files as well. See the
 49clock.awk, ensemble.awk, etf.awk, itf.awk and tdta.awk scripts for
 50further information. A line in the file is produced at each valid update
 51received from a configured radio clock. Data are at present recorded for
 52several radios. The first part of each data line is similar for all
 53radios, e.g.:
 54
 55  49234 60517.826 127.127.4.1   93 247 16:48:21.814
 56
 57  49234             modified Julian day number
 58  60517.826         time of day (s) past midnight UTC
 59  127.127.4.1       receiver identifier (Spectracom 8170/Netclock-2)
 60  93 247 16:48:21.814  timecode (format varies)
 61
 62In the case of the Austron GPS receiver, a good deal of additional
 63information is extracted from the radio, as described below. The formats
 64shown consist of one line with all the fields shown in order. The
 65timecode formats specific to each radio follow. See the file
 66README.timecodes for detailed information on the timecode formats used
 67by these radios.
 68
 69Spectracom 8170/Netclock-2 WWVB receiver
 70
 71  49234 60517.826 127.127.4.1 ?A93 247 16:48:21.814
 72
 73  The '?' and 'A' characters are present only when the receiver is
 74  unsynchronized; otherwise, they are replaced by space ' ' characters.
 75
 76IRIG audio decoder
 77
 78  49234 60517.826 127.127.6.0 247 16:48:21?
 79
 80  The '?' character is present only when the receiver is unsynchronized.
 81
 82Austron 2200A/2201A GPS receiver
 83
 84  49234 60580.843 127.127.10.1 93:247:16:49:24.814?
 85
 86  The '?' character is present only when the receiver is unsynchronized.
 87
 88Depending on the installed options, the Austron 2200A/2201A recognizes a
 89number of special commands that report various data items. See the
 90refclock_as2201.c source module for a list of the commands used. These
 91data are collected only if the following line is included in the
 92configuration file ntp.conf:
 93
 94  fudge 127.127.10.1 flag4 1    # enable extended statistics collection
 95
 96The format of each data line returned is summarized in the following
 97list.
 98
 99External time/frequency data (requires input buffer option IN)
100
101These data determine the deviations of external time/frequency inputs
102relative to receiver oscillator time. The following data are typical
103using an external cesium oscillator PPS and 5-MHz outputs.
104
105  49234 60580.843 127.127.10.1 93:247:16:49:24.814 ETF
106
107  -85.9             time interval (ns)
108  -89.0             average time interval (ns)
109  4.0               time interval sigma (ns)
110  +1.510E-11        time interval rate
111  -4.500E-11        deltaf/f
112  +1.592E-11        average deltaf/f
113  5.297E-13         sigma deltaf/f
114  500               number of samples
115
116Model and option identifiers
117
118These data show the receiver model number and option configuration.
119
120  49234 60708.848 127.127.10.1 93:247:16:51:32.817 ID;OPT;VER
121
122  GPS 2201A         model ident (must be "GPS 2200A" or "GPS 2201A")
123  TTY1              rs232 option present (required)
124  TC1               IRIG option present (optional)
125  LORAN             LORAN assist option present (optional)
126  IN                input buffer option present (optional)
127  OUT1              output buffer option present (required)
128  B.00              data processor software version ("B.00" or later)
129  B.00              signal processor software version ("B.00" or later)
130  28-Apr-93         software version date ("28-Apr-93" or later)
131
132Internal time/frequency data
133
134These data determine the deviations of the receiver oscillator with
135respect to satellite time.
136
137  49234 60564.846 127.127.10.1 93:247:16:49:08.816 ITF
138
139  COCO              current mode (must be "COCO")
140  0                 code coast mode (must be zero)
141  +6.6152E-08       code sigma (s)
142  -3.5053E-08       code delta t (s)
143  -4.0361E-11       deltat/t
144  -6.4746E-11       oscillator ageing rate
145  500.00            loop time constant
146  4.984072          electrical tuning (V)
147
148GPS/LORAN ensemble data (requires LORAN assist option LORAN)
149
150These data determine the deviations and weights to calculate ensemble
151time from GPS and LORAN data.
152
153  49234 60596.852 127.127.10.1 93:247:16:49:40.812 LORAN ENSEMBLE
154
155  +9.06E-08         GPS t (s)
156  +3.53E-08         GPS sigma (s)
157  .532              GPS weight
158  +3.71E-08         LORAN t (s)
159  +3.76E-08         LORAN sigma (s)
160  .468              LORAN weight
161  +6.56E-08         ensemble t
162  +6.94E-08         ensemble sigma (s)
163
164LORAN stationkeeping data (requires LORAN assist option LORAN)
165
166These data determine which stations of the LORAN chain are being
167tracked, together with individual signal/noise ratios, deviations and
168weights.
169
170  49234 60532.850 127.127.10.1 93:247:16:48:36.820 LORAN TDATA
171
172  M                 station identifier; data follows
173  OK                status (must be "OK" for tracking)
174  0                 cw flag
175  0                 sw flag
176  1162.17           time of arrival
177  -4.6              snr (-30.0 if not "OK" status)
178  1.67E-07          2-sample phase-time deviation
179  .507              weight (included only if "OK" status)
180  W AQ 0 0 3387.80 -31.0  station identifier and data
181  X OK 0 0 1740.27 -11.2 2.20E-07 .294  station identifier and data
182  Y OK 0 0 2180.71 -4.6 2.68E-07 .198  station identifier and data
183  Z CV 0 0 3392.94 -30.0  station identifier and data
184
185Oscillator status and environment
186
187These data determine the receiver oscillator type, mode, status and
188environment. Nominal operating conditions are shown below.
189
190  49234 60628.847 127.127.10.1 93:247:16:50:12.817 OSC;ET;TEMP
191
192  1121 Software     Control  oscillator model and mode (must be
193                    "Software Control")
194  Locked            status (must be "Locked")
195  4.979905          electrical tuning (V)
196  44.81             oscillator cavity temperature
197
198Receiver position, status and offsets
199
200These data determine the receiver position and elevation, together with
201programmable delay corrections for the antenna cable and receiver.
202
203  49234 60788.847 127.127.10.1 93:247:16:52:52.817 POS;PPS;PPSOFF
204
205  +39:40:48.425     receiver latitude (N)
206  -075:45:02.392    receiver longitude (E)
207  +74.09            receiver elevation (m)
208  Stored            position status (must be "Stored")
209  UTC               PPS/PPM alignment (must be "UTC")
210  0                 receiver delay (ns) (should be zero for calibrated
211                    receiver)
212  200               cable delay (ns)
213  0                 user time bias (ns) (must be zero)
214
215Satellite tracking status
216
217These data determine how many satellites are being tracked. At the
218present state of constellation development, there should be at least
219three visible satellites in view. Much of the time the maximum of
220seven are being tracked; rarely this number drops to two.
221
222  49234 60612.850 127.127.10.1 93:247:16:49:56.820 TRSTAT
223
224  24 T              satellite prn and status (T = track, A = acquire)
225  16 A 13 T 20 T 18 T 07 T 12 T  list continued
226
227UTC leap-second information
228
229These data determine when the next leap second is to occur. The exact
230method to use is obscure.
231
232  49234 60548.847 127.127.10.1 93:247:16:48:52.818 UTC
233
234  -1.2107E-08       A0 term (s)
235  -1.2790E-13       A1 term (s)
236  +9.0000E+00       current leap seconds (s)
237  +2.0480E+05       time for leap seconds (s)
238  +2.0100E+02       week number for delta leap (weeks)
239  +1.9100E+02       week number for future leap (weeks)
240  +4.0000E+00       day number for future leap (days)
241  +9.0000E+00       future leap seconds (s)
242
243David L. Mills
244University of Delaware
245mills@udel.edu
24623 October 1993