NTPsec

a-ntpsec-14-day-stats

Report generated: Tue Jul 7 05:04:56 2020 UTC
Start Time: Tue Jun 23 05:04:32 2020 UTC
End Time: Tue Jul 7 05:04:32 2020 UTC
Report published: Mon Jul 06 22:08:27 2020 PDT
Report Period: 14.0 days
Warning: plots clipped

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 -18.287 -1.828 -1.353 0.048 1.273 1.669 5.411 2.626 3.497 0.874 -0.006 µs -4.966 23.64
Local Clock Frequency Offset -1.567 -1.514 -1.256 -0.749 -0.508 -0.456 -0.436 0.748 1.058 0.225 -0.786 ppm -105.7 556.1

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 148.000 242.000 287.000 421.000 629.000 754.000 6,188.000 342.000 512.000 136.368 437.042 ns 28.34 479.8

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 64.000 79.000 181.000 358.000 688.000 15,425.000 279.000 624.000 318.762 211.280 10e-12 20.85 621.8

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 -18.287 -1.828 -1.353 0.048 1.273 1.669 5.411 2.626 3.497 0.874 -0.006 µs -4.966 23.64

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 -1.567 -1.514 -1.256 -0.749 -0.508 -0.456 -0.436 0.748 1.058 0.225 -0.786 ppm -105.7 556.1
Temp ZONE0 61.224 61.762 62.300 64.452 67.142 68.756 69.294 4.842 6.994 1.519 64.429 °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 12.000 12.000 4.000 5.000 1.270 9.639 nSat 305.6 2145
TDOP 0.540 0.550 0.600 0.830 1.280 1.550 1.810 0.680 1.000 0.217 0.864 36.65 149.3

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 192.168.1.11

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 -91.309 -1.248 -0.016 0.056 0.856 1.788 3.420 0.873 3.036 1.086 0.122 ms -71.7 5733

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 -49.259 -1.316 -0.018 0.055 0.105 0.150 0.640 0.123 1.465 0.725 0.021 ms -58.37 3461

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 -4.797 -2.768 -2.278 -1.093 1.658 2.494 4.941 3.936 5.262 1.247 -0.768 ms -8.111 19.88

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) -1.413 2.061 2.249 2.595 3.036 3.277 14,315.182 0.787 1.217 276.626 7.962 ms 47.87 2480

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) 1.550 2.104 3.145 3.685 4.241 4.588 52.547 1.096 2.484 1.811 3.741 ms 28.64 730

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 -45.628 2.040 2.255 2.599 3.062 3.354 14.584 0.807 1.314 0.937 2.602 ms -32.65 2006

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 1.225 1.773 2.082 3.473 4.739 5.436 6.496 2.657 3.663 0.805 3.505 ms 47.79 197

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) -12.032 1.765 2.063 2.537 3.016 3.317 4.779 0.952 1.552 0.455 2.528 ms 91.7 762.8

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) -15.032 -7.834 -5.745 1.820 5.045 9.270 14.753 10.790 17.104 3.537 0.803 ms -3.344 9.54

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 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) -73.584 -57.977 -55.054 -48.774 -42.914 -41.011 14,650.925 12.140 16.966 19.287 -48.816 ms 677.6 5.48e+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) -18.288 -1.829 -1.354 0.049 1.274 1.671 14,700,036.970 2.628 3.500 53,024.516 191.261 µs 273.2 7.576e+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 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 0.000 0.014 0.028 0.147 8.684 9.492 191.364 8.656 9.477 4.696 1.332 ms 20.23 745.2

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 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 0.000 0.016 0.033 0.140 8.682 9.389 140.077 8.648 9.373 3.906 1.317 ms 13.33 433.3

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 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 0.000 0.243 0.338 1.631 10.190 15.000 249.154 9.852 14.757 8.773 3.519 ms 18.72 502.1

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 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) 0.000 0.188 0.296 1.591 9.541 17.132 235.474 9.245 16.944 10.259 3.540 ms 12.72 247.5

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 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 0.283 0.415 1.727 9.792 26.572 249.123 9.377 26.289 11.227 3.983 ms 11.32 193.4

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 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 0.000 0.214 0.368 1.895 12.716 88.290 266.569 12.348 88.076 17.443 5.563 ms 6.81 79.86

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 0.000 0.275 0.424 2.137 10.637 17.496 235.940 10.213 17.221 10.429 4.312 ms 12.29 229.9

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 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 0.233 0.350 1.563 9.650 19.474 254.831 9.300 19.241 12.256 3.772 ms 11.21 187

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) 0.000 0.264 0.388 1.802 10.287 33.602 283.986 9.899 33.337 13.298 4.340 ms 11.75 204.2

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 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 0.316 0.467 1.218 3.418 6.303 14,695.975 2.951 5.987 30.449 1.651 ms 346.2 1.343e+05

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 0.156 0.212 0.404 0.797 1.044 13.402 0.585 0.888 0.232 0.444 µs 17.14 611.4

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.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -1.567 -1.514 -1.256 -0.749 -0.508 -0.456 -0.436 0.748 1.058 0.225 -0.786 ppm -105.7 556.1
Local Clock Time Offset -18.287 -1.828 -1.353 0.048 1.273 1.669 5.411 2.626 3.497 0.874 -0.006 µs -4.966 23.64
Local RMS Frequency Jitter 0.000 64.000 79.000 181.000 358.000 688.000 15,425.000 279.000 624.000 318.762 211.280 10e-12 20.85 621.8
Local RMS Time Jitter 148.000 242.000 287.000 421.000 629.000 754.000 6,188.000 342.000 512.000 136.368 437.042 ns 28.34 479.8
Server Jitter 192.168.1.11 0.000 0.014 0.028 0.147 8.684 9.492 191.364 8.656 9.477 4.696 1.332 ms 20.23 745.2
Server Jitter 192.168.1.12 0.000 0.016 0.033 0.140 8.682 9.389 140.077 8.648 9.373 3.906 1.317 ms 13.33 433.3
Server Jitter 2001:1948:210:2::4 0.000 0.243 0.338 1.631 10.190 15.000 249.154 9.852 14.757 8.773 3.519 ms 18.72 502.1
Server Jitter 2001:470:0:50::2 (clock.fmt.he.net) 0.000 0.188 0.296 1.591 9.541 17.132 235.474 9.245 16.944 10.259 3.540 ms 12.72 247.5
Server Jitter 2001:470:e815::24 (pi4.rellim.com) 0.000 0.283 0.415 1.727 9.792 26.572 249.123 9.377 26.289 11.227 3.983 ms 11.32 193.4
Server Jitter 216.218.254.202 0.000 0.214 0.368 1.895 12.716 88.290 266.569 12.348 88.076 17.443 5.563 ms 6.81 79.86
Server Jitter 2405:fc00:0:1::123 0.000 0.275 0.424 2.137 10.637 17.496 235.940 10.213 17.221 10.429 4.312 ms 12.29 229.9
Server Jitter 2604:a880:1:20::17:5001 (ntp1.glypnod.com) 0.000 0.233 0.350 1.563 9.650 19.474 254.831 9.300 19.241 12.256 3.772 ms 11.21 187
Server Jitter 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) 0.000 0.264 0.388 1.802 10.287 33.602 283.986 9.899 33.337 13.298 4.340 ms 11.75 204.2
Server Jitter SHM(0) 0.000 0.316 0.467 1.218 3.418 6.303 14,695.975 2.951 5.987 30.449 1.651 ms 346.2 1.343e+05
Server Jitter SHM(1) 0.000 0.156 0.212 0.404 0.797 1.044 13.402 0.585 0.888 0.232 0.444 µs 17.14 611.4
Server Offset 192.168.1.11 -91.309 -1.248 -0.016 0.056 0.856 1.788 3.420 0.873 3.036 1.086 0.122 ms -71.7 5733
Server Offset 192.168.1.12 -49.259 -1.316 -0.018 0.055 0.105 0.150 0.640 0.123 1.465 0.725 0.021 ms -58.37 3461
Server Offset 2001:1948:210:2::4 -4.797 -2.768 -2.278 -1.093 1.658 2.494 4.941 3.936 5.262 1.247 -0.768 ms -8.111 19.88
Server Offset 2001:470:0:50::2 (clock.fmt.he.net) -1.413 2.061 2.249 2.595 3.036 3.277 14,315.182 0.787 1.217 276.626 7.962 ms 47.87 2480
Server Offset 2001:470:e815::24 (pi4.rellim.com) 1.550 2.104 3.145 3.685 4.241 4.588 52.547 1.096 2.484 1.811 3.741 ms 28.64 730
Server Offset 216.218.254.202 -45.628 2.040 2.255 2.599 3.062 3.354 14.584 0.807 1.314 0.937 2.602 ms -32.65 2006
Server Offset 2405:fc00:0:1::123 1.225 1.773 2.082 3.473 4.739 5.436 6.496 2.657 3.663 0.805 3.505 ms 47.79 197
Server Offset 2604:a880:1:20::17:5001 (ntp1.glypnod.com) -12.032 1.765 2.063 2.537 3.016 3.317 4.779 0.952 1.552 0.455 2.528 ms 91.7 762.8
Server Offset 2a03:b0c0:1:d0::1f9:f001 (ntp2.glypnod.com) -15.032 -7.834 -5.745 1.820 5.045 9.270 14.753 10.790 17.104 3.537 0.803 ms -3.344 9.54
Server Offset SHM(0) -73.584 -57.977 -55.054 -48.774 -42.914 -41.011 14,650.925 12.140 16.966 19.287 -48.816 ms 677.6 5.48e+05
Server Offset SHM(1) -18.288 -1.829 -1.354 0.049 1.274 1.671 14,700,036.970 2.628 3.500 53,024.516 191.261 µs 273.2 7.576e+04
TDOP 0.540 0.550 0.600 0.830 1.280 1.550 1.810 0.680 1.000 0.217 0.864 36.65 149.3
Temp ZONE0 61.224 61.762 62.300 64.452 67.142 68.756 69.294 4.842 6.994 1.519 64.429 °C
nSats 6.000 7.000 8.000 10.000 12.000 12.000 12.000 4.000 5.000 1.270 9.639 nSat 305.6 2145
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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