NTPsec

time.achjoj.info

Report generated: Fri May 29 10:33:02 2026 UTC
Start Time: Thu May 28 08:09:02 2026 UTC
End Time: Fri May 29 10:33:02 2026 UTC
Report Period: 1.1 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 -16.075 -7.193 -4.062 -0.037 2.632 5.864 14.829 6.694 13.057 2.201 -0.220 ms -5.15 18.88
Local Clock Frequency Offset 10.074 15.193 17.063 21.241 35.301 45.075 59.120 18.238 29.882 6.362 23.475 ppm 29.12 119.3

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 0.531 0.638 0.805 1.487 3.205 4.218 5.674 2.400 3.579 0.778 1.690 ms 6.478 21.67

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 0.125 0.160 0.208 0.456 2.365 4.231 10.889 2.157 4.070 0.867 0.765 ppm 3.726 27.94

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 -16.075 -7.193 -4.062 -0.037 2.632 5.864 14.829 6.694 13.057 2.201 -0.220 ms -5.15 18.88

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 10.074 15.193 17.063 21.241 35.301 45.075 59.120 18.238 29.882 6.362 23.475 ppm 29.12 119.3
Temp /dev/sdb 33.000 33.000 33.000 34.000 35.000 35.000 35.000 2.000 2.000 0.602 33.745 °C
Temp LM0 17.000 18.000 18.000 21.000 23.000 24.000 25.000 5.000 6.000 1.505 20.605 °C
Temp LM1 17.000 17.000 18.000 20.000 22.000 23.000 24.000 4.000 6.000 1.372 19.704 °C
Temp LM2 50.000 51.000 51.000 52.000 53.000 54.000 54.000 2.000 3.000 0.726 51.825 °C
Temp LM3 21.000 21.000 21.000 22.500 24.000 24.500 24.500 3.000 3.500 0.807 22.420 °C
Temp LM4 21.000 21.000 21.000 22.500 24.000 24.500 24.500 3.000 3.500 0.853 22.475 °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 4.000 5.000 6.000 8.000 9.000 10.000 11.000 3.000 5.000 1.135 7.682 nSat 209.2 1304
TDOP 0.600 0.670 0.730 1.080 1.960 2.850 3.280 1.230 2.180 0.410 1.177 14.26 57.96

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. Smaller numbers are better. TDOP ranges from 1 (ideal), 2 to 5 (good), to greater than 20 (poor). Some GNSS receivers report TDOP less than one which is theoretically impossible.



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 150.254.190.51

peer offset 150.254.190.51 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 150.254.190.51 -18.862 -17.371 -10.626 -3.577 1.653 4.825 9.223 12.279 22.196 3.641 -3.933 ms -15.83 55.12

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 153.19.250.123

peer offset 153.19.250.123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 153.19.250.123 -18.988 -16.601 -10.858 -4.797 0.233 4.710 7.985 11.091 21.311 3.432 -4.974 ms -22.35 80.88

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 193.110.137.171

peer offset 193.110.137.171 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 193.110.137.171 -21.250 -18.293 -11.567 -4.766 0.653 4.771 5.773 12.220 23.063 3.829 -5.259 ms -21.24 78.19

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 194.146.251.100

peer offset 194.146.251.100 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 194.146.251.100 -18.074 -17.261 -12.413 -4.888 0.653 3.976 6.478 13.066 21.237 3.679 -5.306 ms -22.36 80.43

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 194.146.251.101

peer offset 194.146.251.101 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 194.146.251.101 -19.452 -16.563 -12.446 -4.936 0.521 4.276 7.861 12.967 20.838 3.751 -5.270 ms -21.6 77.61

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 194.29.130.252

peer offset 194.29.130.252 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 194.29.130.252 -16.181 -15.915 -11.056 -4.966 0.850 5.005 8.146 11.906 20.921 3.612 -5.010 ms -20.8 71.54

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 195.187.245.55

peer offset 195.187.245.55 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 195.187.245.55 -18.818 -16.663 -12.027 -5.108 0.063 3.089 7.570 12.090 19.752 3.610 -5.500 ms -23.96 86.7

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 213.135.57.60

peer offset 213.135.57.60 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 213.135.57.60 -17.973 -17.130 -12.966 -5.013 0.430 4.396 7.799 13.395 21.526 3.851 -5.449 ms -21.77 78.12

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) -11.847 -3.943 -0.478 4.780 17.138 20.666 24.556 17.616 24.609 5.307 5.943 ms 1.189 4.117

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 150.254.190.51

peer jitter 150.254.190.51 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 150.254.190.51 0.565 0.743 1.000 2.719 9.850 17.288 18.634 8.850 16.545 3.182 3.803 ms 2.88 11.25

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 153.19.250.123

peer jitter 153.19.250.123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 153.19.250.123 0.362 0.529 0.834 2.238 7.577 11.390 15.825 6.743 10.860 2.305 2.972 ms 3.189 13.25

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 193.110.137.171

peer jitter 193.110.137.171 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 193.110.137.171 0.422 0.635 0.909 2.461 7.636 14.141 23.278 6.727 13.506 2.709 3.223 ms 4.036 23.86

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 194.146.251.100

peer jitter 194.146.251.100 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 194.146.251.100 0.317 0.512 0.868 2.458 9.211 15.587 17.818 8.343 15.076 2.816 3.312 ms 3.017 12.1

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 194.146.251.101

peer jitter 194.146.251.101 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 194.146.251.101 0.521 0.727 0.979 2.721 9.886 15.430 19.225 8.907 14.703 2.725 3.413 ms 3.386 14.39

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 194.29.130.252

peer jitter 194.29.130.252 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 194.29.130.252 0.391 0.500 0.913 2.833 11.306 19.695 22.472 10.393 19.195 3.479 3.887 ms 2.895 12.29

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 195.187.245.55

peer jitter 195.187.245.55 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 195.187.245.55 0.374 0.462 0.837 2.450 7.868 14.972 22.400 7.031 14.510 2.637 3.190 ms 3.64 19.38

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 213.135.57.60

peer jitter 213.135.57.60 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 213.135.57.60 0.676 0.742 1.031 2.533 9.317 15.126 17.543 8.286 14.383 2.801 3.461 ms 2.914 11.09

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) 0.287 0.632 0.901 2.109 5.203 7.161 11.203 4.301 6.529 1.364 2.439 ms 4.478 16.14

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 10.074 15.193 17.063 21.241 35.301 45.075 59.120 18.238 29.882 6.362 23.475 ppm 29.12 119.3
Local Clock Time Offset -16.075 -7.193 -4.062 -0.037 2.632 5.864 14.829 6.694 13.057 2.201 -0.220 ms -5.15 18.88
Local RMS Frequency Jitter 0.125 0.160 0.208 0.456 2.365 4.231 10.889 2.157 4.070 0.867 0.765 ppm 3.726 27.94
Local RMS Time Jitter 0.531 0.638 0.805 1.487 3.205 4.218 5.674 2.400 3.579 0.778 1.690 ms 6.478 21.67
Server Jitter 150.254.190.51 0.565 0.743 1.000 2.719 9.850 17.288 18.634 8.850 16.545 3.182 3.803 ms 2.88 11.25
Server Jitter 153.19.250.123 0.362 0.529 0.834 2.238 7.577 11.390 15.825 6.743 10.860 2.305 2.972 ms 3.189 13.25
Server Jitter 193.110.137.171 0.422 0.635 0.909 2.461 7.636 14.141 23.278 6.727 13.506 2.709 3.223 ms 4.036 23.86
Server Jitter 194.146.251.100 0.317 0.512 0.868 2.458 9.211 15.587 17.818 8.343 15.076 2.816 3.312 ms 3.017 12.1
Server Jitter 194.146.251.101 0.521 0.727 0.979 2.721 9.886 15.430 19.225 8.907 14.703 2.725 3.413 ms 3.386 14.39
Server Jitter 194.29.130.252 0.391 0.500 0.913 2.833 11.306 19.695 22.472 10.393 19.195 3.479 3.887 ms 2.895 12.29
Server Jitter 195.187.245.55 0.374 0.462 0.837 2.450 7.868 14.972 22.400 7.031 14.510 2.637 3.190 ms 3.64 19.38
Server Jitter 213.135.57.60 0.676 0.742 1.031 2.533 9.317 15.126 17.543 8.286 14.383 2.801 3.461 ms 2.914 11.09
Server Jitter SHM(0) 0.287 0.632 0.901 2.109 5.203 7.161 11.203 4.301 6.529 1.364 2.439 ms 4.478 16.14
Server Offset 150.254.190.51 -18.862 -17.371 -10.626 -3.577 1.653 4.825 9.223 12.279 22.196 3.641 -3.933 ms -15.83 55.12
Server Offset 153.19.250.123 -18.988 -16.601 -10.858 -4.797 0.233 4.710 7.985 11.091 21.311 3.432 -4.974 ms -22.35 80.88
Server Offset 193.110.137.171 -21.250 -18.293 -11.567 -4.766 0.653 4.771 5.773 12.220 23.063 3.829 -5.259 ms -21.24 78.19
Server Offset 194.146.251.100 -18.074 -17.261 -12.413 -4.888 0.653 3.976 6.478 13.066 21.237 3.679 -5.306 ms -22.36 80.43
Server Offset 194.146.251.101 -19.452 -16.563 -12.446 -4.936 0.521 4.276 7.861 12.967 20.838 3.751 -5.270 ms -21.6 77.61
Server Offset 194.29.130.252 -16.181 -15.915 -11.056 -4.966 0.850 5.005 8.146 11.906 20.921 3.612 -5.010 ms -20.8 71.54
Server Offset 195.187.245.55 -18.818 -16.663 -12.027 -5.108 0.063 3.089 7.570 12.090 19.752 3.610 -5.500 ms -23.96 86.7
Server Offset 213.135.57.60 -17.973 -17.130 -12.966 -5.013 0.430 4.396 7.799 13.395 21.526 3.851 -5.449 ms -21.77 78.12
Server Offset SHM(0) -11.847 -3.943 -0.478 4.780 17.138 20.666 24.556 17.616 24.609 5.307 5.943 ms 1.189 4.117
TDOP 0.600 0.670 0.730 1.080 1.960 2.850 3.280 1.230 2.180 0.410 1.177 14.26 57.96
Temp /dev/sdb 33.000 33.000 33.000 34.000 35.000 35.000 35.000 2.000 2.000 0.602 33.745 °C
Temp LM0 17.000 18.000 18.000 21.000 23.000 24.000 25.000 5.000 6.000 1.505 20.605 °C
Temp LM1 17.000 17.000 18.000 20.000 22.000 23.000 24.000 4.000 6.000 1.372 19.704 °C
Temp LM2 50.000 51.000 51.000 52.000 53.000 54.000 54.000 2.000 3.000 0.726 51.825 °C
Temp LM3 21.000 21.000 21.000 22.500 24.000 24.500 24.500 3.000 3.500 0.807 22.420 °C
Temp LM4 21.000 21.000 21.000 22.500 24.000 24.500 24.500 3.000 3.500 0.853 22.475 °C
nSats 4.000 5.000 6.000 8.000 9.000 10.000 11.000 3.000 5.000 1.135 7.682 nSat 209.2 1304
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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