NTPsec

c-ntpsec-72-hour-stats

Report generated: Wed Nov 20 16:12:19 2019 UTC
Start Time: Sun Nov 17 16:12:16 2019 UTC
End Time: Wed Nov 20 16:12:16 2019 UTC
Report published: Wed Nov 20 08:13:38 2019 PST
Report Period: 3.0 days

Local Clock Time/Frequency Offsets

local offset plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Time Offset -852.000 -510.000 -365.000 4.000 425.000 600.000 1,009.000 790.000 1,110.000 239.878 13.110 ns -3.488 8.39
Local Clock Frequency Offset -6.873 -6.870 -6.863 -6.824 -6.782 -6.780 -6.778 0.081 0.091 0.023 -6.824 ppm -2.728e+07 8.212e+09

The time and frequency offsets between the ntpd calculated time and the local system clock. Showing frequency offset (red, in parts per million, scale on right) and the time offset (blue, in μs, scale on left). Quick changes in time offset will lead to larger frequency offsets.

These are fields 3 (time) and 4 (frequency) from the loopstats log file.



Local RMS Time Jitter

local jitter plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Time Jitter 84.000 109.000 128.000 182.000 253.000 287.000 382.000 125.000 178.000 37.786 185.311 ns 71.73 335.2

The RMS Jitter of the local clock offset. In other words, how fast the local clock offset is changing.

Lower is better. An ideal system would be a horizontal line at 0μs.

RMS jitter is field 5 in the loopstats log file.



Local RMS Frequency Jitter

local stability plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local RMS Frequency Jitter 23.000 29.000 35.000 53.000 89.000 109.000 174.000 54.000 80.000 17.175 56.593 10e-12 20.18 75.94

The RMS Frequency Jitter (aka wander) of the local clock's frequency. In other words, how fast the local clock changes frequency.

Lower is better. An ideal clock would be a horizontal line at 0ppm.

RMS Frequency Jitter is field 6 in the loopstats log file.



Local Clock Time Offset Histogram

local offset histogram plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Offset -852.000 -510.000 -365.000 4.000 425.000 600.000 1,009.000 790.000 1,110.000 239.878 13.110 ns -3.488 8.39

The clock offsets of the local clock as a histogram.

The Local Clock Offset is field 3 from the loopstats log file.



Local Temperatures

local temps plot

Local temperatures. These will be site-specific depending upon what temperature sensors you collect data from. Temperature changes affect the local clock crystal frequency and stability. The math of how temperature changes frequency is complex, and also depends on crystal aging. So there is no easy way to correct for it in software. This is the single most important component of frequency drift.

The Local Temperatures are from field 3 from the tempstats log file.



Local Frequency/Temp

local freq temps plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -6.873 -6.870 -6.863 -6.824 -6.782 -6.780 -6.778 0.081 0.091 0.023 -6.824 ppm -2.728e+07 8.212e+09
Temp ZONE0 62.300 62.838 63.376 64.452 65.528 66.066 66.604 2.152 3.228 0.790 64.590 °C

The frequency offsets and temperatures. Showing frequency offset (red, in parts per million, scale on right) and the temperatures.

These are field 4 (frequency) from the loopstats log file, and field 3 from the tempstats log file.



Local GPS

local gps plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
nSats 0.000 7.000 7.000 10.000 11.000 12.000 12.000 4.000 5.000 1.276 9.443 nSat 281 1920
TDOP 0.500 0.550 0.600 0.800 1.370 1.730 2.400 0.770 1.180 0.257 0.875 22.36 84.27

Local GPS. The Time Dilution of Precision (TDOP) is plotted in blue. The number of visible satellites (nSat) is plotted in red.

TDOP is field 3, and nSats is field 4, from the gpsd log file. The gpsd log file is created by the ntploggps program.

TDOP is a dimensionless error factor. TDOP ranges from 1 to greater than 20. 1 denotes the highest possible confidence level. 2 to 5 is good. Greater than 20 means there will be significant inaccuracy and error.



Server Offsets

peer offsets plot

The offset of all refclocks and servers. This can be useful to see if offset changes are happening in a single clock or all clocks together.

Clock Offset is field 5 in the peerstats log file.



Server Offset 162.159.200.1

peer offset 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 162.159.200.1 -17.991 -16.455 -16.218 -10.180 -2.958 -1.515 -0.417 13.261 14.941 3.780 -10.256 ms -62.02 270.7

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 173.11.101.155

peer offset 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 173.11.101.155 -2.270 -1.004 -0.317 0.334 1.152 1.759 2.515 1.469 2.763 0.479 0.355 ms -0.7088 7.232

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 178.62.68.79

peer offset 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 178.62.68.79 -8.307 -4.457 -0.531 4.472 9.047 10.920 12.386 9.578 15.377 2.851 4.012 ms 0.6511 5.383

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 192.168.1.10

peer offset 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.10 -88.324 18.975 51.705 95.235 128.373 153.117 226.368 76.668 134.142 25.896 93.176 µs 24.74 85.82

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2001:470:e815::24 (pi4.rellim.com)

peer offset 2001:470:e815::24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:470:e815::24 (pi4.rellim.com) 3.114 3.512 3.814 4.318 5.021 5.515 7.813 1.207 2.004 0.396 4.351 ms 1027 1.063e+04

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 204.123.2.5

peer offset 204.123.2.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.123.2.5 0.054 1.546 2.063 2.448 2.951 3.177 3.660 0.887 1.630 0.332 2.456 ms 279.2 1890

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2405:fc00:0:1::123

peer offset 2405:fc00:0:1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2405:fc00:0:1::123 -2.868 -2.387 -2.185 0.011 0.868 1.373 1.813 3.053 3.760 0.835 -0.173 ms -6.719 21.86

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com)

peer offset 2604:a880:1:20::17:5001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) -0.129 0.278 0.888 2.077 3.073 3.571 4.686 2.185 3.293 0.627 2.042 ms 18.05 59.06

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset SHM(0)

peer offset SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(0) -72.920 -67.472 -64.650 -55.445 -46.561 -43.810 -41.613 18.089 23.662 5.507 -55.581 ms -1398 1.588e+04

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset SHM(1)

peer offset SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(1) -853.000 -511.000 -366.000 5.000 426.000 600.000 1,010.000 792.000 1,111.000 240.646 13.127 ns -3.49 8.384

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Jitters

peer jitters plot

The RMS Jitter of all refclocks and servers. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 162.159.200.1

peer jitter 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 162.159.200.1 0.131 0.229 0.362 2.268 9.764 16.047 114.158 9.402 15.818 6.203 3.711 ms 11.82 209.4

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 173.11.101.155

peer jitter 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 173.11.101.155 0.174 0.405 0.574 2.095 11.798 15.842 186.180 11.224 15.437 7.067 3.736 ms 18.03 464

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 178.62.68.79

peer jitter 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 178.62.68.79 0.255 0.342 0.529 3.005 10.461 12.410 13.483 9.932 12.068 3.228 3.953 ms 1.661 4.158

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 192.168.1.10

peer jitter 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.10 0.010 0.020 0.033 0.138 8.653 9.252 13.510 8.619 9.231 2.754 1.451 ms 0.4727 3.186

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2001:470:e815::24 (pi4.rellim.com)

peer jitter 2001:470:e815::24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.135 0.266 0.428 2.303 15.681 170.115 192.983 15.253 169.849 26.167 8.422 ms 3.121 21.17

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 204.123.2.5

peer jitter 204.123.2.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.123.2.5 0.208 0.236 0.398 2.520 9.669 12.285 16.098 9.271 12.050 3.175 3.821 ms 1.71 4.522

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2405:fc00:0:1::123

peer jitter 2405:fc00:0:1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2405:fc00:0:1::123 0.107 0.233 0.394 2.366 76.977 172.392 227.394 76.582 172.159 33.388 11.520 ms 2 12.33

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com)

peer jitter 2604:a880:1:20::17:5001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.158 0.246 0.381 2.259 13.366 162.471 190.016 12.985 162.225 21.261 6.968 ms 4.472 36.56

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter SHM(0)

peer jitter SHM(0) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter SHM(0) 0.093 0.318 0.594 2.629 6.903 8.657 12.903 6.309 8.339 2.047 3.088 ms 2.496 6.532

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter SHM(1)

peer jitter SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter SHM(1) 36.000 72.000 101.000 203.000 428.000 545.000 783.000 327.000 473.000 102.139 225.679 ns 6.535 20.83

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -6.873 -6.870 -6.863 -6.824 -6.782 -6.780 -6.778 0.081 0.091 0.023 -6.824 ppm -2.728e+07 8.212e+09
Local Clock Time Offset -852.000 -510.000 -365.000 4.000 425.000 600.000 1,009.000 790.000 1,110.000 239.878 13.110 ns -3.488 8.39
Local RMS Frequency Jitter 23.000 29.000 35.000 53.000 89.000 109.000 174.000 54.000 80.000 17.175 56.593 10e-12 20.18 75.94
Local RMS Time Jitter 84.000 109.000 128.000 182.000 253.000 287.000 382.000 125.000 178.000 37.786 185.311 ns 71.73 335.2
Server Jitter 162.159.200.1 0.131 0.229 0.362 2.268 9.764 16.047 114.158 9.402 15.818 6.203 3.711 ms 11.82 209.4
Server Jitter 173.11.101.155 0.174 0.405 0.574 2.095 11.798 15.842 186.180 11.224 15.437 7.067 3.736 ms 18.03 464
Server Jitter 178.62.68.79 0.255 0.342 0.529 3.005 10.461 12.410 13.483 9.932 12.068 3.228 3.953 ms 1.661 4.158
Server Jitter 192.168.1.10 0.010 0.020 0.033 0.138 8.653 9.252 13.510 8.619 9.231 2.754 1.451 ms 0.4727 3.186
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.135 0.266 0.428 2.303 15.681 170.115 192.983 15.253 169.849 26.167 8.422 ms 3.121 21.17
Server Jitter 204.123.2.5 0.208 0.236 0.398 2.520 9.669 12.285 16.098 9.271 12.050 3.175 3.821 ms 1.71 4.522
Server Jitter 2405:fc00:0:1::123 0.107 0.233 0.394 2.366 76.977 172.392 227.394 76.582 172.159 33.388 11.520 ms 2 12.33
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.158 0.246 0.381 2.259 13.366 162.471 190.016 12.985 162.225 21.261 6.968 ms 4.472 36.56
Server Jitter SHM(0) 0.093 0.318 0.594 2.629 6.903 8.657 12.903 6.309 8.339 2.047 3.088 ms 2.496 6.532
Server Jitter SHM(1) 36.000 72.000 101.000 203.000 428.000 545.000 783.000 327.000 473.000 102.139 225.679 ns 6.535 20.83
Server Offset 162.159.200.1 -17.991 -16.455 -16.218 -10.180 -2.958 -1.515 -0.417 13.261 14.941 3.780 -10.256 ms -62.02 270.7
Server Offset 173.11.101.155 -2.270 -1.004 -0.317 0.334 1.152 1.759 2.515 1.469 2.763 0.479 0.355 ms -0.7088 7.232
Server Offset 178.62.68.79 -8.307 -4.457 -0.531 4.472 9.047 10.920 12.386 9.578 15.377 2.851 4.012 ms 0.6511 5.383
Server Offset 192.168.1.10 -88.324 18.975 51.705 95.235 128.373 153.117 226.368 76.668 134.142 25.896 93.176 µs 24.74 85.82
Server Offset 2001:470:e815::24 (pi4.rellim.com) 3.114 3.512 3.814 4.318 5.021 5.515 7.813 1.207 2.004 0.396 4.351 ms 1027 1.063e+04
Server Offset 204.123.2.5 0.054 1.546 2.063 2.448 2.951 3.177 3.660 0.887 1.630 0.332 2.456 ms 279.2 1890
Server Offset 2405:fc00:0:1::123 -2.868 -2.387 -2.185 0.011 0.868 1.373 1.813 3.053 3.760 0.835 -0.173 ms -6.719 21.86
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) -0.129 0.278 0.888 2.077 3.073 3.571 4.686 2.185 3.293 0.627 2.042 ms 18.05 59.06
Server Offset SHM(0) -72.920 -67.472 -64.650 -55.445 -46.561 -43.810 -41.613 18.089 23.662 5.507 -55.581 ms -1398 1.588e+04
Server Offset SHM(1) -853.000 -511.000 -366.000 5.000 426.000 600.000 1,010.000 792.000 1,111.000 240.646 13.127 ns -3.49 8.384
TDOP 0.500 0.550 0.600 0.800 1.370 1.730 2.400 0.770 1.180 0.257 0.875 22.36 84.27
Temp ZONE0 62.300 62.838 63.376 64.452 65.528 66.066 66.604 2.152 3.228 0.790 64.590 °C
nSats 0.000 7.000 7.000 10.000 11.000 12.000 12.000 4.000 5.000 1.276 9.443 nSat 281 1920
Summary as CSV file


Glossary:

frequency offset:
The difference between the ntpd calculated frequency and the local system clock frequency (usually in parts per million, ppm)
jitter, dispersion:
The short term change in a value. NTP measures Local Time Jitter, Refclock Jitter, and Server Jitter in seconds. Local Frequency Jitter is in ppm or ppb.
kurtosis, Kurt:
The kurtosis of a random variable X is the fourth standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of kurtosis. A normal distribution has a kurtosis of three. NIST describes a kurtosis over three as "heavy tailed" and one under three as "light tailed".
ms, millisecond:
One thousandth of a second = 0.001 seconds, 1e-3 seconds
mu, mean:
The arithmetic mean: the sum of all the values divided by the number of values. The formula for mu is: "mu = (∑xi) / N". Where xi denotes the data points and N is the number of data points.
ns, nanosecond:
One billionth of a second, also one thousandth of a microsecond, 0.000000001 seconds and 1e-9 seconds.
percentile:
The value below which a given percentage of values fall.
ppb, parts per billion:
Ratio between two values. These following are all the same: 1 ppb, one in one billion, 1/1,000,000,000, 0.000,000,001, 1e-9 and 0.000,000,1%
ppm, parts per million:
Ratio between two values. These following are all the same: 1 ppm, one in one million, 1/1,000,000, 0.000,001, and 0.000,1%
‰, parts per thousand:
Ratio between two values. These following are all the same: 1 ‰. one in one thousand, 1/1,000, 0.001, and 0.1%
refclock:
Reference clock, a local GPS module or other local source of time.
remote clock:
Any clock reached over the network, LAN or WAN. Also called a peer or server.
time offset:
The difference between the ntpd calculated time and the local system clock's time. Also called phase offset.
σ, sigma:
Sigma denotes the standard deviation (SD) and is centered on the arithmetic mean of the data set. The SD is simply the square root of the variance of the data set. Two sigma is simply twice the standard deviation. Three sigma is three times sigma. Smaller is better.
The formula for sigma is: "σ = √[ ∑(xi-mu)^2 / N ]". Where xi denotes the data points and N is the number of data points.
skewness, Skew:
The skewness of a random variable X is the third standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of skewness. Wikipedia describes it best: "The qualitative interpretation of the skew is complicated and unintuitive."
A normal distribution has a skewness of zero.
upstream clock:
Any server or reference clock used as a source of time.
µs, us, microsecond:
One millionth of a second, also one thousandth of a millisecond, 0.000,001 seconds, and 1e-6 seconds.



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