NTPsec

A-ntpsec-1-hour-stats

Report generated: Wed Oct 23 21:02:07 2019 UTC
Start Time: Wed Oct 23 20:01:37 2019 UTC
End Time: Wed Oct 23 21:02:05 2019 UTC
Report published: Wed Oct 23 14:02:20 2019 PDT
Report Period: 0.0 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 -734.000 -643.000 -555.000 -246.000 58.000 130.000 270.000 613.000 773.000 182.695 -236.912 ns -19.17 63.86
Local Clock Frequency Offset -538.971 -538.940 -538.849 -532.623 -526.154 -525.925 -525.864 12.695 13.015 4.474 -532.580 ppb -1.73e+06 2.077e+08

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 83.000 87.000 117.000 174.000 239.000 257.000 275.000 122.000 170.000 36.225 175.198 ns 68.05 309.2

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 28.000 31.000 35.000 63.000 115.000 124.000 125.000 80.000 93.000 25.558 68.846 10e-12 10.53 31.72

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 -734.000 -643.000 -555.000 -246.000 58.000 130.000 270.000 613.000 773.000 182.695 -236.912 ns -19.17 63.86

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 -538.971 -538.940 -538.849 -532.623 -526.154 -525.925 -525.864 12.695 13.015 4.474 -532.580 ppb -1.73e+06 2.077e+08
Temp ZONE0 59.610 59.610 59.610 60.148 60.686 60.686 60.686 1.076 1.076 0.238 60.184 °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 9.000 9.000 10.000 11.000 12.000 12.000 12.000 2.000 3.000 0.822 10.917 nSat 1886 2.359e+04
TDOP 0.570 0.570 0.580 0.640 0.860 0.980 0.980 0.280 0.410 0.106 0.678 175.8 1062

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 104.131.155.175

peer offset 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 104.131.155.175 2.385 2.385 2.385 3.147 6.789 6.789 6.789 4.404 4.404 1.189 3.375 ms 13.73 52.71

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 3.284 3.284 3.284 4.892 4.892 4.892 4.892 1.608 1.608 0.804 4.088 ms 80.44 379.7

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 192.168.1.11

peer offset 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.11 -164.745 -164.745 -104.362 39.030 135.990 165.637 165.637 240.352 330.382 72.441 27.625 µs -2.465 5.974

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 192.168.1.12

peer offset 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.12 -393.601 -393.601 -289.124 -77.691 143.894 259.573 259.573 433.018 653.174 127.731 -63.664 µs -7.949 22.26

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 203.123.48.219

peer offset 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 203.123.48.219 2.518 2.518 2.518 3.267 3.530 3.530 3.530 1.013 1.013 0.279 3.198 ms 1176 1.261e+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 204.17.205.24

peer offset 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.17.205.24 1.046 1.046 1.046 1.670 2.522 2.522 2.522 1.476 1.476 0.457 1.732 ms 30.16 110.5

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 216.218.192.202

peer offset 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.192.202 2.142 2.142 2.142 2.655 2.964 2.964 2.964 0.822 0.822 0.225 2.664 ms 1314 1.461e+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 216.218.254.202

peer offset 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.254.202 2.059 2.059 2.059 2.635 3.253 3.253 3.253 1.195 1.195 0.382 2.623 ms 219.3 1396

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) -67.934 -65.206 -60.852 -56.091 -53.478 -52.676 -51.727 7.374 12.529 2.575 -56.771 ms -1.231e+04 2.855e+05

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) -735.000 -644.000 -556.000 -247.000 59.000 131.000 271.000 615.000 775.000 183.011 -237.683 ns -19.21 63.96

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 104.131.155.175

peer jitter 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 104.131.155.175 0.592 0.592 0.592 2.014 4.087 4.087 4.087 3.496 3.496 1.234 2.199 ms 2.964 6.039

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 2.288 2.288 2.288 4.097 4.097 4.097 4.097 1.809 1.809 0.904 3.193 ms 23.79 80.42

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 192.168.1.11

peer jitter 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.11 0.130 0.130 0.156 0.579 75.344 75.590 75.590 75.188 75.460 21.491 8.146 ms 0.6843 4.36

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 192.168.1.12

peer jitter 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.12 0.164 0.164 0.189 0.621 75.241 75.397 75.397 75.052 75.234 25.814 12.123 ms 0.2722 2.597

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 203.123.48.219

peer jitter 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 203.123.48.219 1.393 1.393 1.393 2.911 9.248 9.248 9.248 7.855 7.855 3.059 4.500 ms 2.133 4.274

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 204.17.205.24

peer jitter 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.17.205.24 1.040 1.040 1.040 1.614 2.996 2.996 2.996 1.956 1.956 0.551 1.636 ms 14.84 52.52

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 216.218.192.202

peer jitter 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.192.202 0.531 0.531 0.531 1.585 5.672 5.672 5.672 5.141 5.141 1.256 1.936 ms 3.587 12.03

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 216.218.254.202

peer jitter 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.254.202 0.683 0.683 0.683 1.725 7.783 7.783 7.783 7.100 7.100 2.864 3.280 ms 1.216 2.304

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) 0.177 0.369 0.534 1.331 3.667 7.539 9.886 3.133 7.170 1.343 1.782 ms 3.319 13.93

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) 53.000 66.000 84.000 162.000 323.000 401.000 565.000 239.000 335.000 76.175 180.767 ns 7.989 27.58

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 -538.971 -538.940 -538.849 -532.623 -526.154 -525.925 -525.864 12.695 13.015 4.474 -532.580 ppb -1.73e+06 2.077e+08
Local Clock Time Offset -734.000 -643.000 -555.000 -246.000 58.000 130.000 270.000 613.000 773.000 182.695 -236.912 ns -19.17 63.86
Local RMS Frequency Jitter 28.000 31.000 35.000 63.000 115.000 124.000 125.000 80.000 93.000 25.558 68.846 10e-12 10.53 31.72
Local RMS Time Jitter 83.000 87.000 117.000 174.000 239.000 257.000 275.000 122.000 170.000 36.225 175.198 ns 68.05 309.2
Server Jitter 104.131.155.175 0.592 0.592 0.592 2.014 4.087 4.087 4.087 3.496 3.496 1.234 2.199 ms 2.964 6.039
Server Jitter 178.62.68.79 2.288 2.288 2.288 4.097 4.097 4.097 4.097 1.809 1.809 0.904 3.193 ms 23.79 80.42
Server Jitter 192.168.1.11 0.130 0.130 0.156 0.579 75.344 75.590 75.590 75.188 75.460 21.491 8.146 ms 0.6843 4.36
Server Jitter 192.168.1.12 0.164 0.164 0.189 0.621 75.241 75.397 75.397 75.052 75.234 25.814 12.123 ms 0.2722 2.597
Server Jitter 203.123.48.219 1.393 1.393 1.393 2.911 9.248 9.248 9.248 7.855 7.855 3.059 4.500 ms 2.133 4.274
Server Jitter 204.17.205.24 1.040 1.040 1.040 1.614 2.996 2.996 2.996 1.956 1.956 0.551 1.636 ms 14.84 52.52
Server Jitter 216.218.192.202 0.531 0.531 0.531 1.585 5.672 5.672 5.672 5.141 5.141 1.256 1.936 ms 3.587 12.03
Server Jitter 216.218.254.202 0.683 0.683 0.683 1.725 7.783 7.783 7.783 7.100 7.100 2.864 3.280 ms 1.216 2.304
Server Jitter SHM(0) 0.177 0.369 0.534 1.331 3.667 7.539 9.886 3.133 7.170 1.343 1.782 ms 3.319 13.93
Server Jitter SHM(1) 53.000 66.000 84.000 162.000 323.000 401.000 565.000 239.000 335.000 76.175 180.767 ns 7.989 27.58
Server Offset 104.131.155.175 2.385 2.385 2.385 3.147 6.789 6.789 6.789 4.404 4.404 1.189 3.375 ms 13.73 52.71
Server Offset 178.62.68.79 3.284 3.284 3.284 4.892 4.892 4.892 4.892 1.608 1.608 0.804 4.088 ms 80.44 379.7
Server Offset 192.168.1.11 -164.745 -164.745 -104.362 39.030 135.990 165.637 165.637 240.352 330.382 72.441 27.625 µs -2.465 5.974
Server Offset 192.168.1.12 -393.601 -393.601 -289.124 -77.691 143.894 259.573 259.573 433.018 653.174 127.731 -63.664 µs -7.949 22.26
Server Offset 203.123.48.219 2.518 2.518 2.518 3.267 3.530 3.530 3.530 1.013 1.013 0.279 3.198 ms 1176 1.261e+04
Server Offset 204.17.205.24 1.046 1.046 1.046 1.670 2.522 2.522 2.522 1.476 1.476 0.457 1.732 ms 30.16 110.5
Server Offset 216.218.192.202 2.142 2.142 2.142 2.655 2.964 2.964 2.964 0.822 0.822 0.225 2.664 ms 1314 1.461e+04
Server Offset 216.218.254.202 2.059 2.059 2.059 2.635 3.253 3.253 3.253 1.195 1.195 0.382 2.623 ms 219.3 1396
Server Offset SHM(0) -67.934 -65.206 -60.852 -56.091 -53.478 -52.676 -51.727 7.374 12.529 2.575 -56.771 ms -1.231e+04 2.855e+05
Server Offset SHM(1) -735.000 -644.000 -556.000 -247.000 59.000 131.000 271.000 615.000 775.000 183.011 -237.683 ns -19.21 63.96
TDOP 0.570 0.570 0.580 0.640 0.860 0.980 0.980 0.280 0.410 0.106 0.678 175.8 1062
Temp ZONE0 59.610 59.610 59.610 60.148 60.686 60.686 60.686 1.076 1.076 0.238 60.184 °C
nSats 9.000 9.000 10.000 11.000 12.000 12.000 12.000 2.000 3.000 0.822 10.917 nSat 1886 2.359e+04
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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