NTPsec

Kong

Report generated: Fri Jan 17 06:49:01 2025 UTC
Start Time: Thu Jan 16 06:49:00 2025 UTC
End Time: Fri Jan 17 06:49:00 2025 UTC
Report Period: 1.0 days
Warning: plots clipped

Daily stats   Weekly stats   Live GNSS Data   24 Hour Scatter Plots: ( )

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 -392.600 -207.561 -45.571 -2.389 45.409 192.578 329.089 90.980 400.139 53.564 -0.820 µs -0.5088 23.2
Local Clock Frequency Offset 11.661 11.687 11.738 12.089 13.950 13.987 14.001 2.212 2.300 0.901 12.581 ppm 0.7176 1.663

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 10.102 11.879 13.768 22.291 42.944 58.023 70.701 29.176 46.144 8.867 23.831 µs 1.966 8.609

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 4.982 5.649 6.407 11.593 82.149 122.462 131.771 75.743 116.812 23.562 19.084 ppb 3.133 12.39

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 -392.600 -207.561 -45.571 -2.389 45.409 192.578 329.089 90.980 400.139 53.564 -0.820 µs -0.5088 23.2

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 11.661 11.687 11.738 12.089 13.950 13.987 14.001 2.212 2.300 0.901 12.581 ppm 0.7176 1.663
Temp /dev/sda 44.000 44.000 45.000 47.000 49.000 49.000 49.000 4.000 5.000 1.499 46.920 °C
Temp /dev/sdb 34.000 34.000 34.000 36.000 38.000 38.000 38.000 4.000 4.000 1.179 36.087 °C
Temp LM0 48.000 49.000 49.000 54.000 57.000 58.000 58.000 8.000 9.000 2.642 53.815 °C
Temp LM1 43.375 43.858 44.413 47.375 75.963 76.962 79.250 31.550 33.105 13.487 55.709 °C
Temp LM10 25.000 25.000 25.000 25.000 25.000 25.140 26.000 0.000 0.140 0.102 25.010 °C
Temp LM11 61.000 62.000 62.000 63.000 64.000 64.000 64.000 2.000 2.000 0.849 62.969 °C
Temp LM12 3.000 4.860 7.000 12.000 19.700 23.000 28.000 12.700 18.140 4.280 12.390 °C
Temp LM13 25.000 25.000 25.000 25.000 25.000 26.000 26.000 0.000 1.000 0.117 25.014 °C
Temp LM14 43.000 43.000 43.000 44.000 46.000 46.000 46.000 3.000 3.000 1.106 44.460 °C
Temp LM15 35.000 36.000 36.000 38.000 65.000 65.140 68.000 29.000 29.140 12.289 45.878 °C
Temp LM16 66.500 67.000 67.000 68.000 69.000 69.500 69.500 2.000 2.500 0.700 68.157 °C
Temp LM17 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 °C
Temp LM18 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 °C
Temp LM19 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 °C
Temp LM2 40.250 41.500 42.500 45.500 75.000 78.605 81.500 32.500 37.105 13.865 54.107 °C
Temp LM20 43.500 43.858 44.375 47.250 76.000 76.980 79.500 31.625 33.122 13.515 55.670 °C
Temp LM21 66.875 67.000 67.250 68.000 69.250 69.500 69.500 2.000 2.500 0.684 68.301 °C
Temp LM22 34.000 34.000 34.000 36.000 38.000 38.000 38.000 4.000 4.000 1.210 36.118 °C
Temp LM23 63.850 64.850 65.850 68.850 69.850 69.850 69.850 4.000 5.000 1.428 68.198 °C
Temp LM3 44.000 44.000 45.000 47.000 49.000 49.000 49.000 4.000 5.000 1.511 46.937 °C
Temp LM4 48.850 48.850 48.850 50.850 52.850 53.990 54.850 4.000 5.140 1.138 50.627 °C
Temp LM5 48.850 48.850 48.850 50.850 52.850 53.990 54.850 4.000 5.140 1.114 50.648 °C
Temp LM6 55.850 56.710 56.850 58.850 63.850 66.130 72.850 7.000 9.420 2.312 59.414 °C
Temp LM7 48.850 48.850 48.850 50.850 52.850 53.990 54.850 4.000 5.140 1.121 50.658 °C
Temp LM8 43.000 43.000 43.000 44.000 46.000 46.000 46.000 3.000 3.000 1.116 44.460 °C
Temp LM9 36.000 36.000 36.500 38.000 52.500 52.500 53.000 16.000 16.500 6.824 42.157 °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 6.000 8.000 9.000 11.000 13.000 14.000 16.000 4.000 6.000 1.353 11.020 nSat 0.2074 3.041
TDOP 0.770 0.840 0.940 1.340 2.470 3.290 5.230 1.530 2.450 0.500 1.476 1.673 6.637

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 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) -403.108 -192.217 -60.941 8.383 87.866 205.312 336.579 148.807 397.529 59.394 9.678 µs -0.567 15.12

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 2001:470:e815::8 (spidey.rellim.com)

peer offset 2001:470:e815::8 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:470:e815::8 (spidey.rellim.com) -759.378 -721.862 -689.510 72.357 700.846 786.120 843.263 1,390.356 1,507.982 358.904 1.615 µs -0.01906 2.849

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 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net)

peer offset 2001:67c:1270:0:dea6:32ff:feaf:803b plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net) -1,030.128 -456.736 -332.010 -86.549 199.270 327.836 471.089 531.280 784.572 174.055 -89.004 µs -0.1724 5.801

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 204.17.205.1

peer offset 204.17.205.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.17.205.1 -986.130 -976.502 -835.510 3.502 356.639 383.393 400.891 1,192.150 1,359.895 320.846 -22.084 µs -1.38 4.847

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 204.17.205.16

peer offset 204.17.205.16 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.17.205.16 -293.704 -166.982 -49.239 14.240 67.279 195.561 393.559 116.519 362.542 53.949 14.506 µs 0.7077 16.73

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 204.17.205.30

peer offset 204.17.205.30 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.17.205.30 -405.228 -208.260 -98.373 -16.797 48.343 149.627 308.314 146.716 357.887 60.748 -18.710 µs -1.028 16.9

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::1 (robusta.dcs1.biz)

peer offset 2405:fc00::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2405:fc00::1 (robusta.dcs1.biz) 1.297 1.396 1.501 1.966 2.608 2.726 2.792 1.107 1.330 0.336 2.002 ms 0.2704 2.351

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) -1.082 -1.041 -0.952 -0.603 -0.148 0.056 0.123 0.804 1.097 0.240 -0.589 ms 0.4869 3.045

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 2606:4700:f1::1 (time.cloudflare.com)

peer offset 2606:4700:f1::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2606:4700:f1::1 (time.cloudflare.com) -0.751 -0.596 -0.323 0.599 0.852 1.001 1.192 1.175 1.598 0.304 0.546 ms -2.397 9.436

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) -149.081 -135.514 -134.146 -130.219 -126.628 -125.402 -123.655 7.518 10.112 2.370 -130.296 ms -0.3348 4.093

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 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) 2.718 3.843 5.240 17.747 72.322 94.419 118.182 67.082 90.576 21.606 25.382 µs 1.583 5.207

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::8 (spidey.rellim.com)

peer jitter 2001:470:e815::8 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:470:e815::8 (spidey.rellim.com) 1.984 2.780 4.092 14.150 54.899 74.503 136.388 50.808 71.723 16.337 18.991 µs 2.236 10.24

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 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net)

peer jitter 2001:67c:1270:0:dea6:32ff:feaf:803b plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net) 0.103 0.146 0.317 1.062 24.715 36.275 38.056 24.398 36.129 8.916 5.464 ms 1.923 5.663

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 204.17.205.1

peer jitter 204.17.205.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.17.205.1 1.592 2.774 4.682 15.502 51.197 86.296 150.344 46.515 83.522 17.211 20.215 µs 2.815 15.29

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 204.17.205.16

peer jitter 204.17.205.16 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.17.205.16 1.967 4.296 6.037 15.406 58.408 98.715 135.954 52.370 94.420 18.880 21.476 µs 2.602 11.38

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 204.17.205.30

peer jitter 204.17.205.30 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.17.205.30 3.563 4.039 6.223 20.289 68.678 112.374 181.045 62.455 108.335 23.635 27.460 µs 2.584 12.81

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::1 (robusta.dcs1.biz)

peer jitter 2405:fc00::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2405:fc00::1 (robusta.dcs1.biz) 0.130 0.184 0.280 0.686 3.524 5.820 7.192 3.244 5.636 1.167 1.131 ms 2.477 9.887

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) 0.181 0.208 0.263 0.597 2.512 3.196 4.463 2.249 2.987 0.715 0.856 ms 2.198 8.403

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 2606:4700:f1::1 (time.cloudflare.com)

peer jitter 2606:4700:f1::1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 0.153 0.181 0.246 0.441 1.062 2.044 6.808 0.816 1.863 0.592 0.577 ms 7.92 78.12

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) 0.099 0.272 0.404 0.972 2.444 3.866 18.595 2.040 3.593 0.856 1.163 ms 6.316 91.37

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 11.661 11.687 11.738 12.089 13.950 13.987 14.001 2.212 2.300 0.901 12.581 ppm 0.7176 1.663
Local Clock Time Offset -392.600 -207.561 -45.571 -2.389 45.409 192.578 329.089 90.980 400.139 53.564 -0.820 µs -0.5088 23.2
Local RMS Frequency Jitter 4.982 5.649 6.407 11.593 82.149 122.462 131.771 75.743 116.812 23.562 19.084 ppb 3.133 12.39
Local RMS Time Jitter 10.102 11.879 13.768 22.291 42.944 58.023 70.701 29.176 46.144 8.867 23.831 µs 1.966 8.609
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 2.718 3.843 5.240 17.747 72.322 94.419 118.182 67.082 90.576 21.606 25.382 µs 1.583 5.207
Server Jitter 2001:470:e815::8 (spidey.rellim.com) 1.984 2.780 4.092 14.150 54.899 74.503 136.388 50.808 71.723 16.337 18.991 µs 2.236 10.24
Server Jitter 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net) 0.103 0.146 0.317 1.062 24.715 36.275 38.056 24.398 36.129 8.916 5.464 ms 1.923 5.663
Server Jitter 204.17.205.1 1.592 2.774 4.682 15.502 51.197 86.296 150.344 46.515 83.522 17.211 20.215 µs 2.815 15.29
Server Jitter 204.17.205.16 1.967 4.296 6.037 15.406 58.408 98.715 135.954 52.370 94.420 18.880 21.476 µs 2.602 11.38
Server Jitter 204.17.205.30 3.563 4.039 6.223 20.289 68.678 112.374 181.045 62.455 108.335 23.635 27.460 µs 2.584 12.81
Server Jitter 2405:fc00::1 (robusta.dcs1.biz) 0.130 0.184 0.280 0.686 3.524 5.820 7.192 3.244 5.636 1.167 1.131 ms 2.477 9.887
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.181 0.208 0.263 0.597 2.512 3.196 4.463 2.249 2.987 0.715 0.856 ms 2.198 8.403
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 0.153 0.181 0.246 0.441 1.062 2.044 6.808 0.816 1.863 0.592 0.577 ms 7.92 78.12
Server Jitter SHM(0) 0.099 0.272 0.404 0.972 2.444 3.866 18.595 2.040 3.593 0.856 1.163 ms 6.316 91.37
Server Offset 2001:470:e815::24 (pi4.rellim.com) -403.108 -192.217 -60.941 8.383 87.866 205.312 336.579 148.807 397.529 59.394 9.678 µs -0.567 15.12
Server Offset 2001:470:e815::8 (spidey.rellim.com) -759.378 -721.862 -689.510 72.357 700.846 786.120 843.263 1,390.356 1,507.982 358.904 1.615 µs -0.01906 2.849
Server Offset 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net) -1,030.128 -456.736 -332.010 -86.549 199.270 327.836 471.089 531.280 784.572 174.055 -89.004 µs -0.1724 5.801
Server Offset 204.17.205.1 -986.130 -976.502 -835.510 3.502 356.639 383.393 400.891 1,192.150 1,359.895 320.846 -22.084 µs -1.38 4.847
Server Offset 204.17.205.16 -293.704 -166.982 -49.239 14.240 67.279 195.561 393.559 116.519 362.542 53.949 14.506 µs 0.7077 16.73
Server Offset 204.17.205.30 -405.228 -208.260 -98.373 -16.797 48.343 149.627 308.314 146.716 357.887 60.748 -18.710 µs -1.028 16.9
Server Offset 2405:fc00::1 (robusta.dcs1.biz) 1.297 1.396 1.501 1.966 2.608 2.726 2.792 1.107 1.330 0.336 2.002 ms 0.2704 2.351
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) -1.082 -1.041 -0.952 -0.603 -0.148 0.056 0.123 0.804 1.097 0.240 -0.589 ms 0.4869 3.045
Server Offset 2606:4700:f1::1 (time.cloudflare.com) -0.751 -0.596 -0.323 0.599 0.852 1.001 1.192 1.175 1.598 0.304 0.546 ms -2.397 9.436
Server Offset SHM(0) -149.081 -135.514 -134.146 -130.219 -126.628 -125.402 -123.655 7.518 10.112 2.370 -130.296 ms -0.3348 4.093
TDOP 0.770 0.840 0.940 1.340 2.470 3.290 5.230 1.530 2.450 0.500 1.476 1.673 6.637
Temp /dev/sda 44.000 44.000 45.000 47.000 49.000 49.000 49.000 4.000 5.000 1.499 46.920 °C
Temp /dev/sdb 34.000 34.000 34.000 36.000 38.000 38.000 38.000 4.000 4.000 1.179 36.087 °C
Temp LM0 48.000 49.000 49.000 54.000 57.000 58.000 58.000 8.000 9.000 2.642 53.815 °C
Temp LM1 43.375 43.858 44.413 47.375 75.963 76.962 79.250 31.550 33.105 13.487 55.709 °C
Temp LM10 25.000 25.000 25.000 25.000 25.000 25.140 26.000 0.000 0.140 0.102 25.010 °C
Temp LM11 61.000 62.000 62.000 63.000 64.000 64.000 64.000 2.000 2.000 0.849 62.969 °C
Temp LM12 3.000 4.860 7.000 12.000 19.700 23.000 28.000 12.700 18.140 4.280 12.390 °C
Temp LM13 25.000 25.000 25.000 25.000 25.000 26.000 26.000 0.000 1.000 0.117 25.014 °C
Temp LM14 43.000 43.000 43.000 44.000 46.000 46.000 46.000 3.000 3.000 1.106 44.460 °C
Temp LM15 35.000 36.000 36.000 38.000 65.000 65.140 68.000 29.000 29.140 12.289 45.878 °C
Temp LM16 66.500 67.000 67.000 68.000 69.000 69.500 69.500 2.000 2.500 0.700 68.157 °C
Temp LM17 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 °C
Temp LM18 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 °C
Temp LM19 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 °C
Temp LM2 40.250 41.500 42.500 45.500 75.000 78.605 81.500 32.500 37.105 13.865 54.107 °C
Temp LM20 43.500 43.858 44.375 47.250 76.000 76.980 79.500 31.625 33.122 13.515 55.670 °C
Temp LM21 66.875 67.000 67.250 68.000 69.250 69.500 69.500 2.000 2.500 0.684 68.301 °C
Temp LM22 34.000 34.000 34.000 36.000 38.000 38.000 38.000 4.000 4.000 1.210 36.118 °C
Temp LM23 63.850 64.850 65.850 68.850 69.850 69.850 69.850 4.000 5.000 1.428 68.198 °C
Temp LM3 44.000 44.000 45.000 47.000 49.000 49.000 49.000 4.000 5.000 1.511 46.937 °C
Temp LM4 48.850 48.850 48.850 50.850 52.850 53.990 54.850 4.000 5.140 1.138 50.627 °C
Temp LM5 48.850 48.850 48.850 50.850 52.850 53.990 54.850 4.000 5.140 1.114 50.648 °C
Temp LM6 55.850 56.710 56.850 58.850 63.850 66.130 72.850 7.000 9.420 2.312 59.414 °C
Temp LM7 48.850 48.850 48.850 50.850 52.850 53.990 54.850 4.000 5.140 1.121 50.658 °C
Temp LM8 43.000 43.000 43.000 44.000 46.000 46.000 46.000 3.000 3.000 1.116 44.460 °C
Temp LM9 36.000 36.000 36.500 38.000 52.500 52.500 53.000 16.000 16.500 6.824 42.157 °C
nSats 6.000 8.000 9.000 11.000 13.000 14.000 16.000 4.000 6.000 1.353 11.020 nSat 0.2074 3.041
Summary as CSV file


This server:

Motherboard:
OS: Gentoo unstable
GPS/PPS server: gpsd
NTP server: NTPsec
../ntp.conf

Notes:

Feb 21 03:28:57 UTC 2019: New install

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 standard Kurtosis. There are other different ways to calculate 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". See [NIST1]
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. See [NIST2]
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.
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 Fisher-Pearson moment of skewness. See [NIST1]. There are other different ways to calculate Skewness.
Some have said: "The qualitative interpretation of the skew is complicated and unintuitive".
A normal distribution has a skewness of zero.
time offset:
The difference between the ntpd calculated time and the local system clock's time. Also called phase offset.
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.

References:

[NIST1]: NIST/SEMATECH e-Handbook of Statistical Methods, 2012
1.3.5.11. Measures of Skewness and Kurtosis
https://www.itl.nist.gov/div898/handbook/eda/section3/eda35b.htm
[NIST]}: NIST/SEMATECH e-Handbook of Statistical Methods, 2012
7.2.6.2. Percentiles
https://www.itl.nist.gov/div898/handbook/prc/section2/prc262.htm


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