NTPsec

A-ntpsec-6-hour-stats

Report generated: Tue Jul 7 05:01:26 2020 UTC
Start Time: Mon Jul 6 23:01:25 2020 UTC
End Time: Tue Jul 7 05:01:25 2020 UTC
Report published: Mon Jul 06 22:01:31 2020 PDT
Report Period: 0.2 days

Local Clock Time/Frequency Offsets

local offset plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Time Offset -2.507 -2.165 -1.778 -0.781 0.893 1.238 2.231 2.671 3.403 0.848 -0.612 µs -9.813 25.87
Local Clock Frequency Offset -1.517 -1.516 -1.515 -1.472 -1.290 -1.278 -1.274 0.225 0.238 0.077 -1.437 ppm -7665 1.519e+05

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 276.000 320.000 368.000 549.000 786.000 897.000 1,009.000 418.000 577.000 127.987 557.117 ns 48.21 202.9

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 78.000 91.000 108.000 238.000 377.000 409.000 452.000 269.000 318.000 86.990 240.221 10e-12 10.83 30.76

The RMS Frequency Jitter (aka wander) of the local clock's frequency. In other words, how fast the local clock changes frequency.

Lower is better. An ideal clock would be a horizontal line at 0ppm.

RMS Frequency Jitter is field 6 in the loopstats log file.



Local Clock Time Offset Histogram

local offset histogram plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Offset -2.507 -2.165 -1.778 -0.781 0.893 1.238 2.231 2.671 3.403 0.848 -0.612 µs -9.813 25.87

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 -1.517 -1.516 -1.515 -1.472 -1.290 -1.278 -1.274 0.225 0.238 0.077 -1.437 ppm -7665 1.519e+05
Temp ZONE0 66.604 67.142 67.680 68.218 68.756 68.756 69.294 1.076 1.614 0.509 68.176 °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 9.000 9.000 9.000 11.000 12.000 12.000 12.000 3.000 3.000 0.867 10.682 nSat 1486 1.721e+04
TDOP 0.580 0.590 0.600 0.790 1.200 1.310 1.330 0.600 0.720 0.182 0.832 56.82 249.8

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 192.168.1.12

peer offset 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.12 13.729 29.917 40.247 87.357 126.305 148.893 162.397 86.058 118.976 24.285 85.939 µs 23.89 82.74

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 2001:1948:210:2::4

peer offset 2001:1948:210:2::4 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:1948:210:2::4 -3.194 -3.194 -2.785 -1.568 0.703 0.876 0.876 3.488 4.069 1.033 -1.384 ms -19.24 59.87

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



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

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

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) 2.016 2.016 2.177 2.612 3.442 3.597 3.597 1.265 1.581 0.333 2.659 ms 364 2716

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2001:470:e815::24 (pi4.rellim.com)

peer offset 2001:470:e815::24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2001:470:e815::24 (pi4.rellim.com) 3.128 3.128 3.354 3.735 4.460 4.883 4.883 1.105 1.755 0.359 3.806 ms 913.5 9067

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 216.218.254.202

peer offset 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.254.202 0.900 0.900 2.327 2.579 3.136 3.864 3.864 0.808 2.964 0.397 2.612 ms 189.9 1146

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset 2405:fc00:0:1::123

peer offset 2405:fc00:0:1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2405:fc00:0:1::123 4.230 4.230 4.579 5.164 5.537 5.884 5.884 0.958 1.654 0.298 5.128 ms 4305 7.055e+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 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) 1.728 1.728 2.222 2.618 3.393 3.795 3.795 1.171 2.067 0.352 2.691 ms 313.8 2234

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



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

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

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -4.483 -4.483 0.160 2.408 3.444 9.392 9.392 3.284 13.875 1.780 2.243 ms 0.7385 10.37

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) -69.871 -60.610 -56.918 -52.425 -45.473 -44.042 -42.817 11.446 16.568 3.645 -51.899 ms -3583 5.529e+04

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Offset SHM(1)

peer offset SHM(1) plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset SHM(1) -2.508 -2.166 -1.779 -0.782 0.894 1.239 2.232 2.673 3.405 0.849 -0.612 µs -9.812 25.86

The offset of a server in seconds. This is useful to see how the measured offset is behaving.

The chart also plots offset±rtt, where rtt is the round trip time to the server. NTP can not really know the offset of a remote chimer, NTP computes it by subtracting rtt/2 from the offset. Plotting the offset±rtt reverses this calculation to more easily see the effects of rtt changes.

Closer to 0s is better. An ideal system would be a horizontal line at 0s. Typical 90% ranges may be: local LAN server 80µs; 90% ranges for WAN server may be 4ms and much larger.

Clock Offset is field 5 in the peerstats log file. The Round Trip Time (rtt) is field 6 in the peerstats log file.



Server Jitters

peer jitters plot

The RMS Jitter of all refclocks and servers. Jitter is the current estimated dispersion, in other words the variation in offset between samples.

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

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 192.168.1.12

peer jitter 192.168.1.12 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.12 0.018 0.034 0.052 0.150 8.524 8.727 8.740 8.472 8.693 2.230 0.951 ms 0.8915 5.065

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 2001:1948:210:2::4

peer jitter 2001:1948:210:2::4 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:1948:210:2::4 0.435 0.435 0.583 2.340 21.607 31.902 31.902 21.024 31.467 5.614 4.490 ms 2.145 9.558

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

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

RMS Jitter is field 8 in the peerstats log file.



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

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

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.232 0.232 0.497 2.318 12.153 48.710 48.710 11.656 48.477 9.432 5.042 ms 2.451 12.35

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

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

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2001:470:e815::24 (pi4.rellim.com)

peer jitter 2001:470:e815::24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.471 0.471 0.568 2.437 21.153 21.483 21.483 20.585 21.012 5.051 4.383 ms 1.87 6.674

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 216.218.254.202

peer jitter 216.218.254.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.254.202 0.367 0.367 0.491 1.931 23.415 23.586 23.586 22.924 23.219 5.698 4.273 ms 1.713 6.514

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

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

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 2405:fc00:0:1::123

peer jitter 2405:fc00:0:1::123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2405:fc00:0:1::123 0.398 0.398 0.552 2.435 7.852 43.137 43.137 7.300 42.738 5.395 3.630 ms 4.957 36.48

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) 0.229 0.229 0.467 2.568 8.866 9.150 9.150 8.398 8.921 2.979 3.960 ms 1.723 3.427

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

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

RMS Jitter is field 8 in the peerstats log file.



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

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

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.400 0.400 0.620 3.138 12.439 33.602 33.602 11.819 33.201 6.081 5.329 ms 2.492 11.39

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

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

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 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) 0.117 0.334 0.463 1.214 3.570 6.821 16.489 3.106 6.487 1.231 1.605 ms 3.465 17.12

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(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) 0.160 0.223 0.283 0.517 0.995 1.254 1.634 0.712 1.031 0.225 0.559 µs 8.887 29.61

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 -1.517 -1.516 -1.515 -1.472 -1.290 -1.278 -1.274 0.225 0.238 0.077 -1.437 ppm -7665 1.519e+05
Local Clock Time Offset -2.507 -2.165 -1.778 -0.781 0.893 1.238 2.231 2.671 3.403 0.848 -0.612 µs -9.813 25.87
Local RMS Frequency Jitter 78.000 91.000 108.000 238.000 377.000 409.000 452.000 269.000 318.000 86.990 240.221 10e-12 10.83 30.76
Local RMS Time Jitter 276.000 320.000 368.000 549.000 786.000 897.000 1,009.000 418.000 577.000 127.987 557.117 ns 48.21 202.9
Server Jitter 192.168.1.12 0.018 0.034 0.052 0.150 8.524 8.727 8.740 8.472 8.693 2.230 0.951 ms 0.8915 5.065
Server Jitter 2001:1948:210:2::4 0.435 0.435 0.583 2.340 21.607 31.902 31.902 21.024 31.467 5.614 4.490 ms 2.145 9.558
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.232 0.232 0.497 2.318 12.153 48.710 48.710 11.656 48.477 9.432 5.042 ms 2.451 12.35
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.471 0.471 0.568 2.437 21.153 21.483 21.483 20.585 21.012 5.051 4.383 ms 1.87 6.674
Server Jitter 216.218.254.202 0.367 0.367 0.491 1.931 23.415 23.586 23.586 22.924 23.219 5.698 4.273 ms 1.713 6.514
Server Jitter 2405:fc00:0:1::123 0.398 0.398 0.552 2.435 7.852 43.137 43.137 7.300 42.738 5.395 3.630 ms 4.957 36.48
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.229 0.229 0.467 2.568 8.866 9.150 9.150 8.398 8.921 2.979 3.960 ms 1.723 3.427
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.400 0.400 0.620 3.138 12.439 33.602 33.602 11.819 33.201 6.081 5.329 ms 2.492 11.39
Server Jitter SHM(0) 0.117 0.334 0.463 1.214 3.570 6.821 16.489 3.106 6.487 1.231 1.605 ms 3.465 17.12
Server Jitter SHM(1) 0.160 0.223 0.283 0.517 0.995 1.254 1.634 0.712 1.031 0.225 0.559 µs 8.887 29.61
Server Offset 192.168.1.12 13.729 29.917 40.247 87.357 126.305 148.893 162.397 86.058 118.976 24.285 85.939 µs 23.89 82.74
Server Offset 2001:1948:210:2::4 -3.194 -3.194 -2.785 -1.568 0.703 0.876 0.876 3.488 4.069 1.033 -1.384 ms -19.24 59.87
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) 2.016 2.016 2.177 2.612 3.442 3.597 3.597 1.265 1.581 0.333 2.659 ms 364 2716
Server Offset 2001:470:e815::24 (pi4.rellim.com) 3.128 3.128 3.354 3.735 4.460 4.883 4.883 1.105 1.755 0.359 3.806 ms 913.5 9067
Server Offset 216.218.254.202 0.900 0.900 2.327 2.579 3.136 3.864 3.864 0.808 2.964 0.397 2.612 ms 189.9 1146
Server Offset 2405:fc00:0:1::123 4.230 4.230 4.579 5.164 5.537 5.884 5.884 0.958 1.654 0.298 5.128 ms 4305 7.055e+04
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 1.728 1.728 2.222 2.618 3.393 3.795 3.795 1.171 2.067 0.352 2.691 ms 313.8 2234
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -4.483 -4.483 0.160 2.408 3.444 9.392 9.392 3.284 13.875 1.780 2.243 ms 0.7385 10.37
Server Offset SHM(0) -69.871 -60.610 -56.918 -52.425 -45.473 -44.042 -42.817 11.446 16.568 3.645 -51.899 ms -3583 5.529e+04
Server Offset SHM(1) -2.508 -2.166 -1.779 -0.782 0.894 1.239 2.232 2.673 3.405 0.849 -0.612 µs -9.812 25.86
TDOP 0.580 0.590 0.600 0.790 1.200 1.310 1.330 0.600 0.720 0.182 0.832 56.82 249.8
Temp ZONE0 66.604 67.142 67.680 68.218 68.756 68.756 69.294 1.076 1.614 0.509 68.176 °C
nSats 9.000 9.000 9.000 11.000 12.000 12.000 12.000 3.000 3.000 0.867 10.682 nSat 1486 1.721e+04
Summary as CSV file


Glossary:

frequency offset:
The difference between the ntpd calculated frequency and the local system clock frequency (usually in parts per million, ppm)
jitter, dispersion:
The short term change in a value. NTP measures Local Time Jitter, Refclock Jitter, and Server Jitter in seconds. Local Frequency Jitter is in ppm or ppb.
kurtosis, Kurt:
The kurtosis of a random variable X is the fourth standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of kurtosis. A normal distribution has a kurtosis of three. NIST describes a kurtosis over three as "heavy tailed" and one under three as "light tailed".
ms, millisecond:
One thousandth of a second = 0.001 seconds, 1e-3 seconds
mu, mean:
The arithmetic mean: the sum of all the values divided by the number of values. The formula for mu is: "mu = (∑xi) / N". Where xi denotes the data points and N is the number of data points.
ns, nanosecond:
One billionth of a second, also one thousandth of a microsecond, 0.000000001 seconds and 1e-9 seconds.
percentile:
The value below which a given percentage of values fall.
ppb, parts per billion:
Ratio between two values. These following are all the same: 1 ppb, one in one billion, 1/1,000,000,000, 0.000,000,001, 1e-9 and 0.000,000,1%
ppm, parts per million:
Ratio between two values. These following are all the same: 1 ppm, one in one million, 1/1,000,000, 0.000,001, and 0.000,1%
‰, parts per thousand:
Ratio between two values. These following are all the same: 1 ‰. one in one thousand, 1/1,000, 0.001, and 0.1%
refclock:
Reference clock, a local GPS module or other local source of time.
remote clock:
Any clock reached over the network, LAN or WAN. Also called a peer or server.
time offset:
The difference between the ntpd calculated time and the local system clock's time. Also called phase offset.
σ, sigma:
Sigma denotes the standard deviation (SD) and is centered on the arithmetic mean of the data set. The SD is simply the square root of the variance of the data set. Two sigma is simply twice the standard deviation. Three sigma is three times sigma. Smaller is better.
The formula for sigma is: "σ = √[ ∑(xi-mu)^2 / N ]". Where xi denotes the data points and N is the number of data points.
skewness, Skew:
The skewness of a random variable X is the third standardized moment and is a dimension-less ratio. ntpviz uses the Pearson's moment coefficient of skewness. Wikipedia describes it best: "The qualitative interpretation of the skew is complicated and unintuitive."
A normal distribution has a skewness of zero.
upstream clock:
Any server or reference clock used as a source of time.
µs, us, microsecond:
One millionth of a second, also one thousandth of a millisecond, 0.000,001 seconds, and 1e-6 seconds.



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