NTPsec

b-ntpsec-72-hour-stats

Report generated: Wed Nov 20 16:11:27 2019 UTC
Start Time: Sun Nov 17 16:11:12 2019 UTC
End Time: Wed Nov 20 16:11:12 2019 UTC
Report published: Wed Nov 20 08:12:16 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 -2,859.000 -562.000 -394.000 -2.000 383.000 542.000 925.000 777.000 1,104.000 239.978 -2.609 ns -4.258 12.29
Local Clock Frequency Offset -5.679 -5.679 -5.676 -5.650 -5.618 -5.613 -5.611 0.059 0.066 0.0181 -5.648 ppm -3.055e+07 9.552e+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 105.000 147.000 171.000 243.000 347.000 399.000 1,428.000 176.000 252.000 59.686 249.119 ns 44.66 246.8

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 24.000 32.000 38.000 54.000 85.000 114.000 2,059.000 47.000 82.000 55.098 59.501 10e-12 21.66 567.3

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 -2,859.000 -562.000 -394.000 -2.000 383.000 542.000 925.000 777.000 1,104.000 239.978 -2.609 ns -4.258 12.29

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 -5.679 -5.679 -5.676 -5.650 -5.618 -5.613 -5.611 0.059 0.066 0.0181 -5.648 ppm -3.055e+07 9.552e+09
Temp ZONE0 58.534 59.072 59.072 60.148 60.148 60.686 60.686 1.076 1.614 0.451 59.774 °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 5.000 7.000 7.000 9.000 11.000 12.000 12.000 4.000 5.000 1.242 9.277 nSat 290.3 2005
TDOP 0.500 0.570 0.600 0.830 1.400 1.730 4.350 0.800 1.160 0.268 0.897 21.62 88.81

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 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 -835.201 -50.173 -14.437 38.681 69.104 154.837 1,440.984 83.541 205.010 56.138 35.763 µs 6.381 182.2

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 2001:470:0:50::2 (clock.fmt.he.net)

peer offset 2001:470:0:50::2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) 0.677 1.411 1.922 2.468 3.394 4.268 6.192 1.472 2.857 0.504 2.544 ms 80.4 412

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) 2.382 3.123 3.579 4.180 5.233 6.709 8.842 1.654 3.586 0.606 4.282 ms 243.4 1641

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 -1.731 -1.420 -1.008 2.543 3.553 5.065 7.896 4.561 6.485 1.320 2.256 ms 1.135 4.715

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) -2.306 -0.528 0.986 2.325 3.526 4.399 6.866 2.541 4.927 0.840 2.285 ms 9.775 30.71

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 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu)

peer offset 2607:f140:ffff:8000:0:8006:0:a plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu) 0.648 1.314 1.791 2.399 3.542 4.758 6.300 1.751 3.444 0.589 2.495 ms 45.91 213.8

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 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com)

peer offset 2a03:b0c0:1:d0::1f9:f001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -11.810 -7.016 -0.990 3.955 7.960 11.087 13.235 8.950 18.103 2.962 3.448 ms -0.1966 5.953

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 76.14.161.109

peer offset 76.14.161.109 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 76.14.161.109 -8.745 -6.220 -2.379 -0.755 1.476 2.876 5.548 3.854 9.096 1.381 -0.678 ms -8.632 34.55

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) -436.839 -411.806 -401.427 -365.537 -325.958 -311.083 -269.653 75.469 100.723 23.303 -364.937 ms -4674 7.87e+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) -2,860.000 -563.000 -395.000 -3.000 384.000 543.000 926.000 779.000 1,106.000 240.740 -2.620 ns -4.257 12.25

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 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 0.000 0.029 0.087 1.103 7.827 56.080 274.798 7.740 56.051 9.039 2.992 ms 15.47 427.3

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 2001:470:0:50::2 (clock.fmt.he.net)

peer jitter 2001:470:0:50::2 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.000 0.448 0.735 2.846 14.580 33.273 52.138 13.845 32.825 6.252 4.914 ms 3.331 21.73

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) 0.000 0.379 0.660 2.823 14.780 56.792 227.070 14.120 56.413 13.043 5.949 ms 7.961 113

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 0.000 0.492 0.809 2.800 11.655 37.962 190.194 10.846 37.471 10.689 4.751 ms 10.76 174.4

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 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) 0.000 0.506 0.737 2.948 13.375 29.174 57.986 12.638 28.668 5.835 4.760 ms 3.853 28.77

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 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu)

peer jitter 2607:f140:ffff:8000:0:8006:0:a plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu) 0.000 0.361 0.652 2.586 11.846 37.957 58.652 11.193 37.596 6.873 4.598 ms 4.114 29.27

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 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com)

peer jitter 2a03:b0c0:1:d0::1f9:f001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.000 0.532 0.827 3.287 15.121 57.533 190.467 14.293 57.001 13.376 6.005 ms 8.208 106.5

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 76.14.161.109

peer jitter 76.14.161.109 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 76.14.161.109 0.000 1.070 2.089 16.231 105.139 120.298 141.934 103.050 119.228 31.447 27.347 ms 1.321 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 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) 0.000 4.655 6.202 11.611 23.010 30.178 56.712 16.808 25.522 5.365 12.752 ms 8.092 28.41

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) 0.000 94.000 125.000 231.000 441.000 559.000 2,359.000 316.000 465.000 103.515 250.538 ns 9.656 61.86

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.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -5.679 -5.679 -5.676 -5.650 -5.618 -5.613 -5.611 0.059 0.066 0.0181 -5.648 ppm -3.055e+07 9.552e+09
Local Clock Time Offset -2,859.000 -562.000 -394.000 -2.000 383.000 542.000 925.000 777.000 1,104.000 239.978 -2.609 ns -4.258 12.29
Local RMS Frequency Jitter 24.000 32.000 38.000 54.000 85.000 114.000 2,059.000 47.000 82.000 55.098 59.501 10e-12 21.66 567.3
Local RMS Time Jitter 105.000 147.000 171.000 243.000 347.000 399.000 1,428.000 176.000 252.000 59.686 249.119 ns 44.66 246.8
Server Jitter 192.168.1.10 0.000 0.029 0.087 1.103 7.827 56.080 274.798 7.740 56.051 9.039 2.992 ms 15.47 427.3
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.000 0.448 0.735 2.846 14.580 33.273 52.138 13.845 32.825 6.252 4.914 ms 3.331 21.73
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.000 0.379 0.660 2.823 14.780 56.792 227.070 14.120 56.413 13.043 5.949 ms 7.961 113
Server Jitter 2405:fc00:0:1::123 0.000 0.492 0.809 2.800 11.655 37.962 190.194 10.846 37.471 10.689 4.751 ms 10.76 174.4
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.000 0.506 0.737 2.948 13.375 29.174 57.986 12.638 28.668 5.835 4.760 ms 3.853 28.77
Server Jitter 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu) 0.000 0.361 0.652 2.586 11.846 37.957 58.652 11.193 37.596 6.873 4.598 ms 4.114 29.27
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.000 0.532 0.827 3.287 15.121 57.533 190.467 14.293 57.001 13.376 6.005 ms 8.208 106.5
Server Jitter 76.14.161.109 0.000 1.070 2.089 16.231 105.139 120.298 141.934 103.050 119.228 31.447 27.347 ms 1.321 4.158
Server Jitter SHM(0) 0.000 4.655 6.202 11.611 23.010 30.178 56.712 16.808 25.522 5.365 12.752 ms 8.092 28.41
Server Jitter SHM(1) 0.000 94.000 125.000 231.000 441.000 559.000 2,359.000 316.000 465.000 103.515 250.538 ns 9.656 61.86
Server Offset 192.168.1.10 -835.201 -50.173 -14.437 38.681 69.104 154.837 1,440.984 83.541 205.010 56.138 35.763 µs 6.381 182.2
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) 0.677 1.411 1.922 2.468 3.394 4.268 6.192 1.472 2.857 0.504 2.544 ms 80.4 412
Server Offset 2001:470:e815::24 (pi4.rellim.com) 2.382 3.123 3.579 4.180 5.233 6.709 8.842 1.654 3.586 0.606 4.282 ms 243.4 1641
Server Offset 2405:fc00:0:1::123 -1.731 -1.420 -1.008 2.543 3.553 5.065 7.896 4.561 6.485 1.320 2.256 ms 1.135 4.715
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) -2.306 -0.528 0.986 2.325 3.526 4.399 6.866 2.541 4.927 0.840 2.285 ms 9.775 30.71
Server Offset 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu) 0.648 1.314 1.791 2.399 3.542 4.758 6.300 1.751 3.444 0.589 2.495 ms 45.91 213.8
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -11.810 -7.016 -0.990 3.955 7.960 11.087 13.235 8.950 18.103 2.962 3.448 ms -0.1966 5.953
Server Offset 76.14.161.109 -8.745 -6.220 -2.379 -0.755 1.476 2.876 5.548 3.854 9.096 1.381 -0.678 ms -8.632 34.55
Server Offset SHM(0) -436.839 -411.806 -401.427 -365.537 -325.958 -311.083 -269.653 75.469 100.723 23.303 -364.937 ms -4674 7.87e+04
Server Offset SHM(1) -2,860.000 -563.000 -395.000 -3.000 384.000 543.000 926.000 779.000 1,106.000 240.740 -2.620 ns -4.257 12.25
TDOP 0.500 0.570 0.600 0.830 1.400 1.730 4.350 0.800 1.160 0.268 0.897 21.62 88.81
Temp ZONE0 58.534 59.072 59.072 60.148 60.148 60.686 60.686 1.076 1.614 0.451 59.774 °C
nSats 5.000 7.000 7.000 9.000 11.000 12.000 12.000 4.000 5.000 1.242 9.277 nSat 290.3 2005
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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