NTPsec

A-ntpsec-7-day-stats

Report generated: Tue May 12 21:11:36 2026 UTC
Start Time: Tue May 5 21:11:33 2026 UTC
End Time: Tue May 12 21:11:33 2026 UTC
Report published: Tue May 12 02:12:13 PM 2026 PDT
Report Period: 7.0 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 -5.450 -1.909 -1.154 0.036 1.036 1.521 14.404 2.190 3.430 0.692 0.003 µs -3.963 17.55
Local Clock Frequency Offset -528.931 -519.867 -480.057 -233.826 -20.386 14.664 24.353 459.671 534.531 142.309 -246.729 ppb -28.65 102.9

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 0.001 0.446 0.526 0.798 1.290 1.590 5.093 0.764 1.144 0.242 0.838 µs 23.79 100

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 0.174 0.203 0.302 0.491 0.644 39.792 0.288 0.470 0.424 0.327 ppb 60.26 4373

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 -5.450 -1.909 -1.154 0.036 1.036 1.521 14.404 2.190 3.430 0.692 0.003 µs -3.963 17.55

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 -528.931 -519.867 -480.057 -233.826 -20.386 14.664 24.353 459.671 534.531 142.309 -246.729 ppb -28.65 102.9
Temp ZONE0 42.932 43.470 44.008 46.160 49.388 49.388 51.540 5.380 5.918 1.610 46.371 °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 7.000 8.000 10.000 12.000 13.000 14.000 4.000 6.000 1.328 9.575 nSat 258.7 1734
TDOP 0.470 0.500 0.530 0.840 1.210 1.360 2.150 0.680 0.860 0.208 0.850 39.13 159.9

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 157.131.224.9

peer offset 157.131.224.9 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 157.131.224.9 -0.782 1.542 2.311 2.918 3.593 4.994 5.773 1.282 3.452 0.534 2.940 ms 105.9 564.6

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 173.11.101.155

peer offset 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 173.11.101.155 -5.816 -4.086 -3.363 -0.250 2.727 4.355 6.904 6.090 8.442 1.881 -0.319 ms -4.972 12.19

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 192.12.19.20

peer offset 192.12.19.20 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.12.19.20 -1.470 0.435 1.444 2.721 3.814 4.920 6.316 2.371 4.485 0.743 2.666 ms 25.01 90.34

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 2001:5a8:601:4005::36

peer offset 2001:5a8:601:4005::36 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:5a8:601:4005::36 0.249 0.563 0.935 1.774 3.516 3.614 3.892 2.582 3.051 0.751 1.968 ms 9.951 31.16

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) 0.468 0.894 1.502 2.755 4.083 4.378 4.790 2.582 3.484 0.936 2.948 ms 16.16 49.08

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) -4.209 1.011 1.778 2.616 4.249 4.656 7.606 2.470 3.645 0.670 2.661 ms 35.56 148.7

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 2607:5300:205:200::7f70

peer offset 2607:5300:205:200::7f70 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2607:5300:205:200::7f70 -0.274 0.909 1.564 2.588 4.541 7.668 10.110 2.977 6.758 1.007 2.740 ms 12.78 58.22

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 2607:5300:205:200::90d0 (fjord.txryan.com)

peer offset 2607:5300:205:200::90d0 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2607:5300:205:200::90d0 (fjord.txryan.com) 0.541 1.409 1.983 2.807 4.167 4.372 5.140 2.185 2.963 0.660 2.923 ms 50.97 217.5

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 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) 0.509 1.142 1.929 2.725 3.912 4.735 7.837 1.982 3.593 0.576 2.731 ms 64.51 303.1

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 50.116.42.84

peer offset 50.116.42.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 50.116.42.84 -0.610 0.058 0.681 1.650 3.428 4.883 5.874 2.747 4.826 0.913 1.870 ms 5.197 15.92

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 52.10.183.132

peer offset 52.10.183.132 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 52.10.183.132 -1.463 0.581 1.460 2.528 4.179 4.725 5.546 2.719 4.144 0.807 2.604 ms 17.77 60.46

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 66.220.9.122

peer offset 66.220.9.122 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 66.220.9.122 0.104 1.041 1.554 2.213 3.478 4.235 7.787 1.924 3.194 0.558 2.252 ms 38.83 173.1

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 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) -135.544 -134.810 -133.455 -130.051 -96.380 -94.963 -92.573 37.075 39.847 12.554 -124.970 ms -1346 1.505e+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) -5.451 -1.910 -1.156 0.037 1.037 1.522 14.405 2.193 3.432 0.693 0.003 µs -3.963 17.51

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 157.131.224.9

peer jitter 157.131.224.9 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 157.131.224.9 0.216 0.356 0.782 2.183 8.139 17.536 51.322 7.357 17.180 3.223 3.034 ms 4.587 41.88

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 173.11.101.155

peer jitter 173.11.101.155 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 173.11.101.155 0.000 1.391 1.763 3.512 10.698 17.866 109.448 8.936 16.475 3.826 4.350 ms 11.95 286.7

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 192.12.19.20

peer jitter 192.12.19.20 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.12.19.20 0.000 0.362 0.795 2.124 11.441 19.803 59.970 10.646 19.441 4.247 3.359 ms 4.986 52.02

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 2001:5a8:601:4005::36

peer jitter 2001:5a8:601:4005::36 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:5a8:601:4005::36 0.000 0.682 0.986 1.963 5.304 11.835 24.082 4.317 11.153 2.305 2.455 ms 6.408 54.03

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 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 0.390 0.599 1.857 6.894 19.630 24.383 6.295 19.240 3.069 2.579 ms 4.244 26.15

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) 0.236 0.499 0.910 2.142 8.929 16.959 31.235 8.019 16.460 3.166 3.139 ms 3.568 20.58

The RMS Jitter of a server. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

Closer to 0s is better. An ideal system would be a horizontal line at 0s.

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2607:5300:205:200::7f70

peer jitter 2607:5300:205:200::7f70 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2607:5300:205:200::7f70 0.265 0.794 1.038 2.372 11.025 17.987 194.836 9.987 17.193 6.982 3.773 ms 16.75 436.4

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 2607:5300:205:200::90d0 (fjord.txryan.com)

peer jitter 2607:5300:205:200::90d0 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2607:5300:205:200::90d0 (fjord.txryan.com) 0.000 0.429 0.769 1.806 7.180 20.378 28.161 6.411 19.949 2.962 2.553 ms 4.631 32.07

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 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 0.584 0.884 2.044 9.308 18.457 86.756 8.424 17.872 4.395 3.201 ms 8.283 133.1

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 50.116.42.84

peer jitter 50.116.42.84 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 50.116.42.84 0.000 0.403 0.737 2.114 10.244 32.572 162.621 9.507 32.168 6.902 3.589 ms 9.142 158.5

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 52.10.183.132

peer jitter 52.10.183.132 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 52.10.183.132 0.000 0.372 0.755 2.040 9.284 21.728 75.126 8.529 21.356 4.201 3.116 ms 5.893 67.87

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 66.220.9.122

peer jitter 66.220.9.122 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 66.220.9.122 0.000 0.337 0.809 2.030 8.770 17.958 43.006 7.961 17.621 3.250 2.974 ms 3.925 27.09

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) 0.000 0.057 0.108 0.477 1.186 1.709 2.805 1.078 1.652 0.353 0.548 ms 3.249 11.71

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 0.290 0.393 0.784 1.624 2.245 7.644 1.231 1.955 0.409 0.870 µs 6.816 31.9

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 -528.931 -519.867 -480.057 -233.826 -20.386 14.664 24.353 459.671 534.531 142.309 -246.729 ppb -28.65 102.9
Local Clock Time Offset -5.450 -1.909 -1.154 0.036 1.036 1.521 14.404 2.190 3.430 0.692 0.003 µs -3.963 17.55
Local RMS Frequency Jitter 0.000 0.174 0.203 0.302 0.491 0.644 39.792 0.288 0.470 0.424 0.327 ppb 60.26 4373
Local RMS Time Jitter 0.001 0.446 0.526 0.798 1.290 1.590 5.093 0.764 1.144 0.242 0.838 µs 23.79 100
Server Jitter 157.131.224.9 0.216 0.356 0.782 2.183 8.139 17.536 51.322 7.357 17.180 3.223 3.034 ms 4.587 41.88
Server Jitter 173.11.101.155 0.000 1.391 1.763 3.512 10.698 17.866 109.448 8.936 16.475 3.826 4.350 ms 11.95 286.7
Server Jitter 192.12.19.20 0.000 0.362 0.795 2.124 11.441 19.803 59.970 10.646 19.441 4.247 3.359 ms 4.986 52.02
Server Jitter 2001:5a8:601:4005::36 0.000 0.682 0.986 1.963 5.304 11.835 24.082 4.317 11.153 2.305 2.455 ms 6.408 54.03
Server Jitter 2606:4700:f1::1 (time.cloudflare.com) 0.000 0.390 0.599 1.857 6.894 19.630 24.383 6.295 19.240 3.069 2.579 ms 4.244 26.15
Server Jitter 2606:4700:f1::123 (time.cloudflare.com) 0.236 0.499 0.910 2.142 8.929 16.959 31.235 8.019 16.460 3.166 3.139 ms 3.568 20.58
Server Jitter 2607:5300:205:200::7f70 0.265 0.794 1.038 2.372 11.025 17.987 194.836 9.987 17.193 6.982 3.773 ms 16.75 436.4
Server Jitter 2607:5300:205:200::90d0 (fjord.txryan.com) 0.000 0.429 0.769 1.806 7.180 20.378 28.161 6.411 19.949 2.962 2.553 ms 4.631 32.07
Server Jitter 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu) 0.000 0.584 0.884 2.044 9.308 18.457 86.756 8.424 17.872 4.395 3.201 ms 8.283 133.1
Server Jitter 50.116.42.84 0.000 0.403 0.737 2.114 10.244 32.572 162.621 9.507 32.168 6.902 3.589 ms 9.142 158.5
Server Jitter 52.10.183.132 0.000 0.372 0.755 2.040 9.284 21.728 75.126 8.529 21.356 4.201 3.116 ms 5.893 67.87
Server Jitter 66.220.9.122 0.000 0.337 0.809 2.030 8.770 17.958 43.006 7.961 17.621 3.250 2.974 ms 3.925 27.09
Server Jitter SHM(0) 0.000 0.057 0.108 0.477 1.186 1.709 2.805 1.078 1.652 0.353 0.548 ms 3.249 11.71
Server Jitter SHM(1) 0.000 0.290 0.393 0.784 1.624 2.245 7.644 1.231 1.955 0.409 0.870 µs 6.816 31.9
Server Offset 157.131.224.9 -0.782 1.542 2.311 2.918 3.593 4.994 5.773 1.282 3.452 0.534 2.940 ms 105.9 564.6
Server Offset 173.11.101.155 -5.816 -4.086 -3.363 -0.250 2.727 4.355 6.904 6.090 8.442 1.881 -0.319 ms -4.972 12.19
Server Offset 192.12.19.20 -1.470 0.435 1.444 2.721 3.814 4.920 6.316 2.371 4.485 0.743 2.666 ms 25.01 90.34
Server Offset 2001:5a8:601:4005::36 0.249 0.563 0.935 1.774 3.516 3.614 3.892 2.582 3.051 0.751 1.968 ms 9.951 31.16
Server Offset 2606:4700:f1::1 (time.cloudflare.com) 0.468 0.894 1.502 2.755 4.083 4.378 4.790 2.582 3.484 0.936 2.948 ms 16.16 49.08
Server Offset 2606:4700:f1::123 (time.cloudflare.com) -4.209 1.011 1.778 2.616 4.249 4.656 7.606 2.470 3.645 0.670 2.661 ms 35.56 148.7
Server Offset 2607:5300:205:200::7f70 -0.274 0.909 1.564 2.588 4.541 7.668 10.110 2.977 6.758 1.007 2.740 ms 12.78 58.22
Server Offset 2607:5300:205:200::90d0 (fjord.txryan.com) 0.541 1.409 1.983 2.807 4.167 4.372 5.140 2.185 2.963 0.660 2.923 ms 50.97 217.5
Server Offset 2607:f140:ffff:8000:0:8006:0:a (ntp1.net.berkeley.edu) 0.509 1.142 1.929 2.725 3.912 4.735 7.837 1.982 3.593 0.576 2.731 ms 64.51 303.1
Server Offset 50.116.42.84 -0.610 0.058 0.681 1.650 3.428 4.883 5.874 2.747 4.826 0.913 1.870 ms 5.197 15.92
Server Offset 52.10.183.132 -1.463 0.581 1.460 2.528 4.179 4.725 5.546 2.719 4.144 0.807 2.604 ms 17.77 60.46
Server Offset 66.220.9.122 0.104 1.041 1.554 2.213 3.478 4.235 7.787 1.924 3.194 0.558 2.252 ms 38.83 173.1
Server Offset SHM(0) -135.544 -134.810 -133.455 -130.051 -96.380 -94.963 -92.573 37.075 39.847 12.554 -124.970 ms -1346 1.505e+04
Server Offset SHM(1) -5.451 -1.910 -1.156 0.037 1.037 1.522 14.405 2.193 3.432 0.693 0.003 µs -3.963 17.51
TDOP 0.470 0.500 0.530 0.840 1.210 1.360 2.150 0.680 0.860 0.208 0.850 39.13 159.9
Temp ZONE0 42.932 43.470 44.008 46.160 49.388 49.388 51.540 5.380 5.918 1.610 46.371 °C
nSats 6.000 7.000 8.000 10.000 12.000 13.000 14.000 4.000 6.000 1.328 9.575 nSat 258.7 1734
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.



This page autogenerated by ntpviz, part of the NTPsec project
html 5    Valid CSS!