NTPsec

A-ntpsec-1-hour-stats

Report generated: Wed Nov 20 17:02:06 2019 UTC
Start Time: Wed Nov 20 16:01:37 2019 UTC
End Time: Wed Nov 20 17:02:05 2019 UTC
Report published: Wed Nov 20 09:02:15 2019 PST
Report Period: 0.0 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 -1,047.000 -800.000 -701.000 -392.000 -50.000 5.000 114.000 651.000 805.000 201.640 -388.033 ns -33.84 127.8
Local Clock Frequency Offset -666.840 -666.656 -665.787 -654.739 -642.685 -641.098 -640.900 23.102 25.558 6.964 -654.710 ppb -8.581e+05 8.156e+07

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 79.000 81.000 91.000 139.000 191.000 220.000 237.000 100.000 139.000 29.641 138.905 ns 61.55 275.2

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 34.000 39.000 48.000 111.000 206.000 231.000 237.000 158.000 192.000 44.217 117.082 10e-12 10 30.62

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 -1,047.000 -800.000 -701.000 -392.000 -50.000 5.000 114.000 651.000 805.000 201.640 -388.033 ns -33.84 127.8

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 -666.840 -666.656 -665.787 -654.739 -642.685 -641.098 -640.900 23.102 25.558 6.964 -654.710 ppb -8.581e+05 8.156e+07
Temp ZONE0 61.224 61.224 61.224 62.300 62.300 62.300 62.300 1.076 1.076 0.359 62.067 °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 10.000 10.000 12.000 12.000 12.000 2.000 3.000 0.629 10.267 nSat 3646 5.664e+04
TDOP 0.500 0.500 0.510 0.670 0.830 0.840 0.840 0.320 0.340 0.075 0.667 516.4 4276

Local GPS. The Time Dilution of Precision (TDOP) is plotted in blue. The number of visible satellites (nSat) is plotted in red.

TDOP is field 3, and nSats is field 4, from the gpsd log file. The gpsd log file is created by the ntploggps program.

TDOP is a dimensionless error factor. TDOP ranges from 1 to greater than 20. 1 denotes the highest possible confidence level. 2 to 5 is good. Greater than 20 means there will be significant inaccuracy and error.



Server Offsets

peer offsets plot

The offset of all refclocks and servers. This can be useful to see if offset changes are happening in a single clock or all clocks together.

Clock Offset is field 5 in the peerstats log file.



Server Offset 192.168.1.11

peer offset 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.11 -16.438 -16.438 13.247 54.082 102.247 265.828 265.828 89.000 282.266 36.313 56.229 µs 5.051 29.54

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 192.168.1.12

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 -77.468 -77.468 -50.376 -12.404 34.372 73.121 73.121 84.748 150.589 26.860 -10.352 µs -6.339 16.71

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

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

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

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



Server Offset 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) 2.484 2.484 2.484 2.680 2.940 2.940 2.940 0.455 0.455 0.150 2.669 ms 4810 8.178e+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 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) 3.452 3.452 3.452 4.319 4.736 4.736 4.736 1.284 1.284 0.301 4.229 ms 2267 3.008e+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 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 2.381 2.381 2.381 2.605 2.792 2.792 2.792 0.411 0.411 0.128 2.591 ms 7247 1.41e+05

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 3.653 3.653 3.653 3.832 4.126 4.126 4.126 0.473 0.473 0.139 3.851 ms 1.918e+04 5.149e+05

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

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

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

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



Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com)

peer offset 2604:a880:1:20::17:5001 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 2.241 2.241 2.241 2.555 2.791 2.791 2.791 0.550 0.550 0.165 2.515 ms 2905 4.185e+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 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) -4.947 -4.947 -4.947 4.559 4.940 4.940 4.940 9.888 9.888 2.898 3.168 ms -1.565 4.483

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) -64.394 -62.076 -57.431 -53.873 -49.740 -48.051 -46.884 7.691 14.025 2.687 -53.926 ms -9420 1.998e+05

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) -1,048.000 -801.000 -702.000 -393.000 -51.000 6.000 115.000 651.000 807.000 201.700 -388.959 ns -33.95 128.3

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 192.168.1.11

peer jitter 192.168.1.11 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.11 0.055 0.055 0.076 1.486 9.953 16.433 16.433 9.877 16.378 3.439 2.713 ms 1.864 7.914

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 192.168.1.12

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 0.048 0.048 0.093 1.989 8.803 9.571 9.571 8.710 9.523 3.222 3.001 ms 0.6831 2.088

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) 0.234 0.234 0.234 1.648 8.804 8.804 8.804 8.570 8.570 3.621 3.651 ms 0.6782 1.528

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) 0.409 0.409 0.409 4.793 12.627 12.627 12.627 12.218 12.218 4.678 4.890 ms 0.8203 2.004

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 0.323 0.323 0.323 1.433 8.409 8.409 8.409 8.086 8.086 2.462 2.172 ms 1.574 4.398

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 0.242 0.242 0.242 0.669 2.717 2.717 2.717 2.475 2.475 0.731 1.013 ms 2.533 6.376

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) 0.521 0.521 0.521 4.311 10.813 10.813 10.813 10.291 10.291 3.894 4.851 ms 0.9349 1.858

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) 0.436 0.436 0.436 3.046 9.201 9.201 9.201 8.765 8.765 2.726 3.269 ms 1.798 4.592

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) 0.102 0.318 0.424 1.108 3.605 6.778 9.059 3.181 6.459 1.266 1.575 ms 2.893 11.49

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) 40.000 55.000 70.000 150.000 334.000 457.000 480.000 264.000 402.000 81.545 168.465 ns 5.648 18.1

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.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -666.840 -666.656 -665.787 -654.739 -642.685 -641.098 -640.900 23.102 25.558 6.964 -654.710 ppb -8.581e+05 8.156e+07
Local Clock Time Offset -1,047.000 -800.000 -701.000 -392.000 -50.000 5.000 114.000 651.000 805.000 201.640 -388.033 ns -33.84 127.8
Local RMS Frequency Jitter 34.000 39.000 48.000 111.000 206.000 231.000 237.000 158.000 192.000 44.217 117.082 10e-12 10 30.62
Local RMS Time Jitter 79.000 81.000 91.000 139.000 191.000 220.000 237.000 100.000 139.000 29.641 138.905 ns 61.55 275.2
Server Jitter 192.168.1.11 0.055 0.055 0.076 1.486 9.953 16.433 16.433 9.877 16.378 3.439 2.713 ms 1.864 7.914
Server Jitter 192.168.1.12 0.048 0.048 0.093 1.989 8.803 9.571 9.571 8.710 9.523 3.222 3.001 ms 0.6831 2.088
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.234 0.234 0.234 1.648 8.804 8.804 8.804 8.570 8.570 3.621 3.651 ms 0.6782 1.528
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.409 0.409 0.409 4.793 12.627 12.627 12.627 12.218 12.218 4.678 4.890 ms 0.8203 2.004
Server Jitter 216.218.254.202 0.323 0.323 0.323 1.433 8.409 8.409 8.409 8.086 8.086 2.462 2.172 ms 1.574 4.398
Server Jitter 2405:fc00:0:1::123 0.242 0.242 0.242 0.669 2.717 2.717 2.717 2.475 2.475 0.731 1.013 ms 2.533 6.376
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.521 0.521 0.521 4.311 10.813 10.813 10.813 10.291 10.291 3.894 4.851 ms 0.9349 1.858
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.436 0.436 0.436 3.046 9.201 9.201 9.201 8.765 8.765 2.726 3.269 ms 1.798 4.592
Server Jitter SHM(0) 0.102 0.318 0.424 1.108 3.605 6.778 9.059 3.181 6.459 1.266 1.575 ms 2.893 11.49
Server Jitter SHM(1) 40.000 55.000 70.000 150.000 334.000 457.000 480.000 264.000 402.000 81.545 168.465 ns 5.648 18.1
Server Offset 192.168.1.11 -16.438 -16.438 13.247 54.082 102.247 265.828 265.828 89.000 282.266 36.313 56.229 µs 5.051 29.54
Server Offset 192.168.1.12 -77.468 -77.468 -50.376 -12.404 34.372 73.121 73.121 84.748 150.589 26.860 -10.352 µs -6.339 16.71
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) 2.484 2.484 2.484 2.680 2.940 2.940 2.940 0.455 0.455 0.150 2.669 ms 4810 8.178e+04
Server Offset 2001:470:e815::24 (pi4.rellim.com) 3.452 3.452 3.452 4.319 4.736 4.736 4.736 1.284 1.284 0.301 4.229 ms 2267 3.008e+04
Server Offset 216.218.254.202 2.381 2.381 2.381 2.605 2.792 2.792 2.792 0.411 0.411 0.128 2.591 ms 7247 1.41e+05
Server Offset 2405:fc00:0:1::123 3.653 3.653 3.653 3.832 4.126 4.126 4.126 0.473 0.473 0.139 3.851 ms 1.918e+04 5.149e+05
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 2.241 2.241 2.241 2.555 2.791 2.791 2.791 0.550 0.550 0.165 2.515 ms 2905 4.185e+04
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -4.947 -4.947 -4.947 4.559 4.940 4.940 4.940 9.888 9.888 2.898 3.168 ms -1.565 4.483
Server Offset SHM(0) -64.394 -62.076 -57.431 -53.873 -49.740 -48.051 -46.884 7.691 14.025 2.687 -53.926 ms -9420 1.998e+05
Server Offset SHM(1) -1,048.000 -801.000 -702.000 -393.000 -51.000 6.000 115.000 651.000 807.000 201.700 -388.959 ns -33.95 128.3
TDOP 0.500 0.500 0.510 0.670 0.830 0.840 0.840 0.320 0.340 0.075 0.667 516.4 4276
Temp ZONE0 61.224 61.224 61.224 62.300 62.300 62.300 62.300 1.076 1.076 0.359 62.067 °C
nSats 9.000 9.000 10.000 10.000 12.000 12.000 12.000 2.000 3.000 0.629 10.267 nSat 3646 5.664e+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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