NTPsec

Kong

Report generated: Tue Feb 11 14:59:01 2025 UTC
Start Time: Tue Feb 4 14:59:00 2025 UTC
End Time: Tue Feb 11 14:59:00 2025 UTC
Report Period: 7.0 days

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 -7.431 -0.235 -0.071 -0.002 0.065 0.235 0.646 0.136 0.471 0.172 -0.006 ms -32.69 1331
Local Clock Frequency Offset 11.052 11.203 11.356 11.544 13.255 13.904 13.946 1.899 2.701 0.536 11.676 ppm 3.405 13.77

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 12.036 15.521 19.423 33.745 78.867 233.802 2,689.005 59.444 218.281 130.441 48.477 µs 14.92 250.8

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 0.000 6.499 8.626 17.603 91.144 178.376 300.033 82.518 171.876 31.232 26.068 ppb 4.19 23.62

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 -7.431 -0.235 -0.071 -0.002 0.065 0.235 0.646 0.136 0.471 0.172 -0.006 ms -32.69 1331

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 11.052 11.203 11.356 11.544 13.255 13.904 13.946 1.899 2.701 0.536 11.676 ppm 3.405 13.77
Temp /dev/sda 42.000 43.000 44.000 46.000 48.000 49.000 50.000 4.000 6.000 1.553 46.063 °C
Temp /dev/sdb 31.000 32.000 33.000 35.000 37.000 38.000 39.000 4.000 6.000 1.414 34.971 °C
Temp LM0 47.000 49.000 49.000 54.000 58.000 59.000 59.000 9.000 10.000 2.920 53.858 °C
Temp LM1 34.750 35.750 36.750 38.875 73.000 74.359 84.750 36.250 38.609 8.686 41.683 °C
Temp LM10 25.000 25.000 25.000 25.000 25.000 25.000 25.000 0.000 0.000 0.000 25.000 °C
Temp LM11 59.000 60.000 60.000 62.000 63.000 63.000 66.000 3.000 3.000 0.752 61.544 °C
Temp LM12 3.000 4.000 7.000 21.000 28.000 33.000 43.000 21.000 29.000 6.548 19.558 °C
Temp LM13 25.000 25.000 25.000 25.000 25.000 25.000 25.000 0.000 0.000 0.000 25.000 °C
Temp LM14 40.000 41.000 42.000 43.000 44.000 45.000 45.000 2.000 4.000 0.863 43.072 °C
Temp LM15 30.000 31.000 32.000 34.000 62.000 63.000 73.000 30.000 32.000 6.954 35.765 °C
Temp LM16 65.000 65.500 66.000 67.000 68.000 68.500 72.500 2.000 3.000 0.638 66.946 °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 34.500 35.750 36.750 39.500 71.750 74.250 84.250 35.000 38.500 8.366 41.947 °C
Temp LM20 34.750 35.750 36.750 38.875 73.000 74.375 84.750 36.250 38.625 8.682 41.670 °C
Temp LM21 65.000 65.750 66.000 67.000 68.000 68.750 72.500 2.000 3.000 0.623 67.084 °C
Temp LM22 31.000 32.000 33.000 35.000 37.000 37.000 39.000 4.000 5.000 1.352 35.016 °C
Temp LM23 62.850 64.850 65.850 67.850 69.850 69.850 71.850 4.000 5.000 1.387 68.007 °C
Temp LM3 42.000 43.000 44.000 46.000 48.000 49.000 50.000 4.000 6.000 1.553 46.072 °C
Temp LM4 46.850 47.850 47.850 49.850 50.850 53.850 56.850 3.000 6.000 1.130 49.678 °C
Temp LM5 46.850 47.850 47.850 49.850 50.850 53.850 56.850 3.000 6.000 1.130 49.696 °C
Temp LM6 54.850 54.850 55.850 57.850 60.850 68.850 73.850 5.000 14.000 2.145 58.125 °C
Temp LM7 46.850 47.850 47.850 49.850 50.850 53.850 56.850 3.000 6.000 1.131 49.699 °C
Temp LM8 40.000 41.000 42.000 43.000 44.000 45.000 45.000 2.000 4.000 0.862 43.070 °C
Temp LM9 30.500 31.500 32.500 34.500 49.675 52.000 53.500 17.175 20.500 4.166 35.251 °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 7.000 7.000 10.000 12.000 14.000 15.000 5.000 7.000 1.494 9.763 nSat 0.2282 3.157
TDOP 0.630 0.810 0.970 1.450 2.850 4.020 28.020 1.880 3.210 0.715 1.612 6.132 114.8

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) -7.239 -0.201 -0.084 0.016 0.116 0.386 0.828 0.200 0.588 0.153 0.016 ms -26.89 1249

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) -7.450 -0.871 -0.563 0.009 0.352 0.468 0.795 0.915 1.339 0.392 -0.024 ms -9.354 167.4

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) -6.876 -0.850 -0.628 -0.275 0.251 17.835 25.640 0.879 18.686 2.879 0.217 ms 6.183 43.33

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 -7.394 -1.340 -1.011 0.026 0.682 0.858 1.163 1.693 2.197 0.486 -0.025 ms -1.522 16.35

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 -7.421 -0.598 -0.144 -0.028 0.061 0.168 0.822 0.205 0.766 0.225 -0.046 ms -20.39 613.4

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) -28.058 -0.399 0.772 1.713 8.104 18.875 27.659 7.332 19.274 3.428 2.338 ms 2.855 30.5

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 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) -7.335 -1.142 -0.824 -0.423 0.114 0.917 3.040 0.938 2.059 0.428 -0.400 ms -1.584 52.95

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) -6.110 0.009 0.151 0.419 0.786 0.952 1.310 0.635 0.943 0.314 0.428 ms -12.34 261.1

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::123 (time.cloudflare.com)

peer offset 2606:4700:f1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2606:4700:f1::123 (time.cloudflare.com) -0.242 0.132 0.292 0.582 9.208 20.086 26.552 8.916 19.954 3.419 1.361 ms 4.758 26.41

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) -179.334 -144.369 -134.477 -128.012 -123.635 -122.085 -119.121 10.842 22.284 3.901 -128.457 ms -1.91 10.93

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) 0.000 6.128 13.081 83.321 161.648 219.121 4,647.385 148.567 212.993 171.959 92.382 µs 19.2 423.2

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) 0.000 0.004 0.008 0.049 0.167 0.216 5.958 0.159 0.212 0.124 0.075 ms 33.98 1479

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) 0.000 0.203 0.282 0.723 6.704 18.823 27.243 6.422 18.620 3.097 1.627 ms 4.981 31.65

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 0.000 5.791 13.308 64.508 179.058 219.782 4,779.919 165.750 213.991 154.764 88.422 µs 23.93 666.5

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 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 0.000 0.009 0.019 0.091 0.193 0.533 6.521 0.175 0.524 0.231 0.110 ms 17.74 408.2

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) 0.000 0.240 0.352 1.590 11.404 26.133 76.952 11.051 25.893 5.384 3.175 ms 6.123 63.73

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 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 0.174 0.265 0.628 2.285 6.284 12.221 2.021 6.109 0.992 0.932 ms 4.641 33.3

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 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) 0.000 0.161 0.216 0.468 1.589 4.145 15.524 1.373 3.984 1.069 0.681 ms 9.14 102.9

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::123 (time.cloudflare.com)

peer jitter 2606:4700:f1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2606:4700:f1::123 (time.cloudflare.com) 0.120 0.173 0.240 0.501 5.972 20.746 25.246 5.732 20.573 3.254 1.276 ms 5.154 31.07

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 0.257 0.364 0.941 6.197 10.072 43.361 5.833 9.815 2.050 1.569 ms 4.444 37.9

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 11.052 11.203 11.356 11.544 13.255 13.904 13.946 1.899 2.701 0.536 11.676 ppm 3.405 13.77
Local Clock Time Offset -7.431 -0.235 -0.071 -0.002 0.065 0.235 0.646 0.136 0.471 0.172 -0.006 ms -32.69 1331
Local RMS Frequency Jitter 0.000 6.499 8.626 17.603 91.144 178.376 300.033 82.518 171.876 31.232 26.068 ppb 4.19 23.62
Local RMS Time Jitter 12.036 15.521 19.423 33.745 78.867 233.802 2,689.005 59.444 218.281 130.441 48.477 µs 14.92 250.8
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.000 6.128 13.081 83.321 161.648 219.121 4,647.385 148.567 212.993 171.959 92.382 µs 19.2 423.2
Server Jitter 2001:470:e815::8 (spidey.rellim.com) 0.000 0.004 0.008 0.049 0.167 0.216 5.958 0.159 0.212 0.124 0.075 ms 33.98 1479
Server Jitter 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net) 0.000 0.203 0.282 0.723 6.704 18.823 27.243 6.422 18.620 3.097 1.627 ms 4.981 31.65
Server Jitter 204.17.205.1 0.000 5.791 13.308 64.508 179.058 219.782 4,779.919 165.750 213.991 154.764 88.422 µs 23.93 666.5
Server Jitter 204.17.205.30 0.000 0.009 0.019 0.091 0.193 0.533 6.521 0.175 0.524 0.231 0.110 ms 17.74 408.2
Server Jitter 2405:fc00::1 (robusta.dcs1.biz) 0.000 0.240 0.352 1.590 11.404 26.133 76.952 11.051 25.893 5.384 3.175 ms 6.123 63.73
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.000 0.174 0.265 0.628 2.285 6.284 12.221 2.021 6.109 0.992 0.932 ms 4.641 33.3
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 0.000 0.161 0.216 0.468 1.589 4.145 15.524 1.373 3.984 1.069 0.681 ms 9.14 102.9
Server Jitter 2606:4700:f1::123 (time.cloudflare.com) 0.120 0.173 0.240 0.501 5.972 20.746 25.246 5.732 20.573 3.254 1.276 ms 5.154 31.07
Server Jitter SHM(0) 0.000 0.257 0.364 0.941 6.197 10.072 43.361 5.833 9.815 2.050 1.569 ms 4.444 37.9
Server Offset 2001:470:e815::24 (pi4.rellim.com) -7.239 -0.201 -0.084 0.016 0.116 0.386 0.828 0.200 0.588 0.153 0.016 ms -26.89 1249
Server Offset 2001:470:e815::8 (spidey.rellim.com) -7.450 -0.871 -0.563 0.009 0.352 0.468 0.795 0.915 1.339 0.392 -0.024 ms -9.354 167.4
Server Offset 2001:67c:1270:0:dea6:32ff:feaf:803b (khronos.mikieboy.net) -6.876 -0.850 -0.628 -0.275 0.251 17.835 25.640 0.879 18.686 2.879 0.217 ms 6.183 43.33
Server Offset 204.17.205.1 -7.394 -1.340 -1.011 0.026 0.682 0.858 1.163 1.693 2.197 0.486 -0.025 ms -1.522 16.35
Server Offset 204.17.205.30 -7.421 -0.598 -0.144 -0.028 0.061 0.168 0.822 0.205 0.766 0.225 -0.046 ms -20.39 613.4
Server Offset 2405:fc00::1 (robusta.dcs1.biz) -28.058 -0.399 0.772 1.713 8.104 18.875 27.659 7.332 19.274 3.428 2.338 ms 2.855 30.5
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) -7.335 -1.142 -0.824 -0.423 0.114 0.917 3.040 0.938 2.059 0.428 -0.400 ms -1.584 52.95
Server Offset 2606:4700:f1::1 (time.cloudflare.com) -6.110 0.009 0.151 0.419 0.786 0.952 1.310 0.635 0.943 0.314 0.428 ms -12.34 261.1
Server Offset 2606:4700:f1::123 (time.cloudflare.com) -0.242 0.132 0.292 0.582 9.208 20.086 26.552 8.916 19.954 3.419 1.361 ms 4.758 26.41
Server Offset SHM(0) -179.334 -144.369 -134.477 -128.012 -123.635 -122.085 -119.121 10.842 22.284 3.901 -128.457 ms -1.91 10.93
TDOP 0.630 0.810 0.970 1.450 2.850 4.020 28.020 1.880 3.210 0.715 1.612 6.132 114.8
Temp /dev/sda 42.000 43.000 44.000 46.000 48.000 49.000 50.000 4.000 6.000 1.553 46.063 °C
Temp /dev/sdb 31.000 32.000 33.000 35.000 37.000 38.000 39.000 4.000 6.000 1.414 34.971 °C
Temp LM0 47.000 49.000 49.000 54.000 58.000 59.000 59.000 9.000 10.000 2.920 53.858 °C
Temp LM1 34.750 35.750 36.750 38.875 73.000 74.359 84.750 36.250 38.609 8.686 41.683 °C
Temp LM10 25.000 25.000 25.000 25.000 25.000 25.000 25.000 0.000 0.000 0.000 25.000 °C
Temp LM11 59.000 60.000 60.000 62.000 63.000 63.000 66.000 3.000 3.000 0.752 61.544 °C
Temp LM12 3.000 4.000 7.000 21.000 28.000 33.000 43.000 21.000 29.000 6.548 19.558 °C
Temp LM13 25.000 25.000 25.000 25.000 25.000 25.000 25.000 0.000 0.000 0.000 25.000 °C
Temp LM14 40.000 41.000 42.000 43.000 44.000 45.000 45.000 2.000 4.000 0.863 43.072 °C
Temp LM15 30.000 31.000 32.000 34.000 62.000 63.000 73.000 30.000 32.000 6.954 35.765 °C
Temp LM16 65.000 65.500 66.000 67.000 68.000 68.500 72.500 2.000 3.000 0.638 66.946 °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 34.500 35.750 36.750 39.500 71.750 74.250 84.250 35.000 38.500 8.366 41.947 °C
Temp LM20 34.750 35.750 36.750 38.875 73.000 74.375 84.750 36.250 38.625 8.682 41.670 °C
Temp LM21 65.000 65.750 66.000 67.000 68.000 68.750 72.500 2.000 3.000 0.623 67.084 °C
Temp LM22 31.000 32.000 33.000 35.000 37.000 37.000 39.000 4.000 5.000 1.352 35.016 °C
Temp LM23 62.850 64.850 65.850 67.850 69.850 69.850 71.850 4.000 5.000 1.387 68.007 °C
Temp LM3 42.000 43.000 44.000 46.000 48.000 49.000 50.000 4.000 6.000 1.553 46.072 °C
Temp LM4 46.850 47.850 47.850 49.850 50.850 53.850 56.850 3.000 6.000 1.130 49.678 °C
Temp LM5 46.850 47.850 47.850 49.850 50.850 53.850 56.850 3.000 6.000 1.130 49.696 °C
Temp LM6 54.850 54.850 55.850 57.850 60.850 68.850 73.850 5.000 14.000 2.145 58.125 °C
Temp LM7 46.850 47.850 47.850 49.850 50.850 53.850 56.850 3.000 6.000 1.131 49.699 °C
Temp LM8 40.000 41.000 42.000 43.000 44.000 45.000 45.000 2.000 4.000 0.862 43.070 °C
Temp LM9 30.500 31.500 32.500 34.500 49.675 52.000 53.500 17.175 20.500 4.166 35.251 °C
nSats 4.000 7.000 7.000 10.000 12.000 14.000 15.000 5.000 7.000 1.494 9.763 nSat 0.2282 3.157
Summary as CSV file


This server:

Motherboard:
OS: Gentoo unstable
GPS:
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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