NTPsec

C-ntpsec-3-hour-stats

Report generated: Thu Aug 5 12:01:18 2021 UTC
Start Time: Thu Aug 5 09:01:18 2021 UTC
End Time: Thu Aug 5 12:01:18 2021 UTC
Report published: Thu Aug 05 05:01:24 2021 PDT
Report Period: 0.1 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 -1,135.000 -884.000 -703.000 -266.000 258.000 436.000 706.000 961.000 1,320.000 286.384 -246.524 ns -11.87 34.51
Local Clock Frequency Offset -4.946 -4.945 -4.944 -4.923 -4.907 -4.906 -4.905 0.037 0.039 0.0121 -4.924 ppm -6.849e+07 2.802e+10

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 104.000 122.000 140.000 192.000 281.000 326.000 409.000 141.000 204.000 43.499 198.705 ns 57.12 257.3

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 37.000 44.000 85.000 136.000 164.000 173.000 92.000 127.000 27.620 87.843 10e-12 17.35 57.95

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 -1,135.000 -884.000 -703.000 -266.000 258.000 436.000 706.000 961.000 1,320.000 286.384 -246.524 ns -11.87 34.51

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 -4.946 -4.945 -4.944 -4.923 -4.907 -4.906 -4.905 0.037 0.039 0.0121 -4.924 ppm -6.849e+07 2.802e+10
Temp ZONE0 58.534 58.534 58.534 59.072 60.148 60.686 60.686 1.614 2.152 0.374 59.215 °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 8.000 8.000 9.000 10.000 12.000 13.000 13.000 3.000 5.000 1.150 9.928 nSat 468.3 3768
TDOP 0.470 0.480 0.530 0.800 1.110 1.210 1.450 0.580 0.730 0.205 0.807 34.22 130.4

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 162.159.200.1

peer offset 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 162.159.200.1 2.611 2.611 2.727 2.998 4.070 4.092 4.092 1.342 1.481 0.316 3.042 ms 671.4 6076

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 -293.896 -293.896 -198.336 283.617 718.641 860.767 860.767 916.977 1,154.663 257.439 255.458 µs 0.09608 2.774

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 192.168.1.10

peer offset 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 192.168.1.10 94.101 105.130 126.265 185.125 245.710 255.187 261.050 119.445 150.057 32.598 185.105 µs 116.2 610.1

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 194.58.202.211

peer offset 194.58.202.211 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 194.58.202.211 5.855 5.855 6.038 6.420 6.709 6.787 6.787 0.671 0.931 0.184 6.393 ms 3.884e+04 1.317e+06

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 194.58.202.219

peer offset 194.58.202.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 194.58.202.219 6.596 6.596 6.648 6.868 7.120 7.156 7.156 0.472 0.560 0.142 6.862 ms 1.051e+05 4.963e+06

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 203.123.48.219

peer offset 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 203.123.48.219 -587.756 -587.756 -467.707 -197.192 -8.673 176.273 176.273 459.034 764.029 161.794 -211.139 µs -19.24 63.54

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 204.17.205.24

peer offset 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.17.205.24 3.618 3.618 3.730 3.970 4.236 4.250 4.250 0.505 0.633 0.141 3.978 ms 2.046e+04 5.611e+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 216.218.192.202

peer offset 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 216.218.192.202 2.653 2.653 2.658 2.900 3.136 3.210 3.210 0.478 0.557 0.138 2.896 ms 8122 1.641e+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 63.145.169.3

peer offset 63.145.169.3 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 63.145.169.3 -74.214 -74.214 -73.377 -60.516 -10.905 -8.434 -8.434 62.472 65.780 16.706 -56.393 ms -95.43 460.2

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 64.62.153.210

peer offset 64.62.153.210 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 64.62.153.210 2.306 2.306 2.435 2.684 3.009 3.045 3.045 0.575 0.739 0.183 2.716 ms 2708 3.813e+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 64.62.194.189

peer offset 64.62.194.189 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 64.62.194.189 5.498 5.498 5.527 5.801 6.272 6.291 6.291 0.745 0.794 0.221 5.809 ms 1.618e+04 4.105e+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 73.158.5.1

peer offset 73.158.5.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 73.158.5.1 -1.366 -1.366 -0.998 -0.156 0.782 0.962 0.962 1.780 2.328 0.467 -0.124 ms -5.904 16.12

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) -67.107 -66.289 -64.100 -56.332 -50.579 -49.149 -47.650 13.521 17.140 4.516 -57.011 ms -2570 3.557e+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) -1,136.000 -885.000 -704.000 -267.000 259.000 437.000 707.000 963.000 1,322.000 286.940 -247.116 ns -11.87 34.49

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 162.159.200.1

peer jitter 162.159.200.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 162.159.200.1 0.216 0.216 0.273 0.927 8.711 8.832 8.832 8.439 8.617 2.627 2.153 ms 0.9986 3.017

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 0.190 0.190 0.264 1.784 13.745 13.820 13.820 13.481 13.629 4.456 4.401 ms 0.8713 2.307

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 192.168.1.10

peer jitter 192.168.1.10 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 192.168.1.10 0.024 0.035 0.053 0.199 7.314 8.735 8.758 7.260 8.700 2.223 0.976 ms 0.8736 4.748

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 194.58.202.211

peer jitter 194.58.202.211 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 194.58.202.211 0.258 0.258 0.280 1.113 8.129 8.775 8.775 7.849 8.516 1.761 1.437 ms 2.722 11.27

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 194.58.202.219

peer jitter 194.58.202.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 194.58.202.219 0.197 0.197 0.221 0.772 6.352 7.373 7.373 6.131 7.175 1.947 1.636 ms 1.369 3.983

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 203.123.48.219

peer jitter 203.123.48.219 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 203.123.48.219 0.130 0.130 0.146 1.168 10.811 11.109 11.109 10.665 10.979 3.631 3.238 ms 0.724 2.076

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

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

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 204.17.205.24

peer jitter 204.17.205.24 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.17.205.24 0.179 0.179 0.211 0.553 8.732 8.831 8.831 8.520 8.652 2.681 1.871 ms 0.7987 2.845

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 216.218.192.202

peer jitter 216.218.192.202 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 216.218.192.202 0.220 0.220 0.235 1.088 9.083 15.342 15.342 8.848 15.122 4.044 3.199 ms 0.6198 2.57

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 63.145.169.3

peer jitter 63.145.169.3 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 63.145.169.3 3.310 3.310 3.857 13.823 57.577 76.025 76.025 53.720 72.715 16.418 19.173 ms 2.324 7.401

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 64.62.153.210

peer jitter 64.62.153.210 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 64.62.153.210 0.280 0.280 0.293 1.478 8.959 9.806 9.806 8.665 9.526 3.171 3.161 ms 0.9069 2.12

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 64.62.194.189

peer jitter 64.62.194.189 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 64.62.194.189 0.265 0.265 0.354 1.178 9.156 9.453 9.453 8.801 9.188 3.288 2.960 ms 0.8812 2.203

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 73.158.5.1

peer jitter 73.158.5.1 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 73.158.5.1 0.534 0.534 0.992 1.983 9.441 9.542 9.542 8.449 9.009 3.267 3.676 ms 1.396 2.776

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) 0.107 0.248 0.377 0.939 3.049 5.540 7.673 2.672 5.292 0.981 1.228 ms 3.393 14.94

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) 55.000 74.000 113.000 250.000 547.000 801.000 1,088.000 434.000 727.000 142.412 279.555 ns 5.386 20.07

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.



Summary


Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Local Clock Frequency Offset -4.946 -4.945 -4.944 -4.923 -4.907 -4.906 -4.905 0.037 0.039 0.0121 -4.924 ppm -6.849e+07 2.802e+10
Local Clock Time Offset -1,135.000 -884.000 -703.000 -266.000 258.000 436.000 706.000 961.000 1,320.000 286.384 -246.524 ns -11.87 34.51
Local RMS Frequency Jitter 34.000 37.000 44.000 85.000 136.000 164.000 173.000 92.000 127.000 27.620 87.843 10e-12 17.35 57.95
Local RMS Time Jitter 104.000 122.000 140.000 192.000 281.000 326.000 409.000 141.000 204.000 43.499 198.705 ns 57.12 257.3
Server Jitter 162.159.200.1 0.216 0.216 0.273 0.927 8.711 8.832 8.832 8.439 8.617 2.627 2.153 ms 0.9986 3.017
Server Jitter 173.11.101.155 0.190 0.190 0.264 1.784 13.745 13.820 13.820 13.481 13.629 4.456 4.401 ms 0.8713 2.307
Server Jitter 192.168.1.10 0.024 0.035 0.053 0.199 7.314 8.735 8.758 7.260 8.700 2.223 0.976 ms 0.8736 4.748
Server Jitter 194.58.202.211 0.258 0.258 0.280 1.113 8.129 8.775 8.775 7.849 8.516 1.761 1.437 ms 2.722 11.27
Server Jitter 194.58.202.219 0.197 0.197 0.221 0.772 6.352 7.373 7.373 6.131 7.175 1.947 1.636 ms 1.369 3.983
Server Jitter 203.123.48.219 0.130 0.130 0.146 1.168 10.811 11.109 11.109 10.665 10.979 3.631 3.238 ms 0.724 2.076
Server Jitter 204.17.205.24 0.179 0.179 0.211 0.553 8.732 8.831 8.831 8.520 8.652 2.681 1.871 ms 0.7987 2.845
Server Jitter 216.218.192.202 0.220 0.220 0.235 1.088 9.083 15.342 15.342 8.848 15.122 4.044 3.199 ms 0.6198 2.57
Server Jitter 63.145.169.3 3.310 3.310 3.857 13.823 57.577 76.025 76.025 53.720 72.715 16.418 19.173 ms 2.324 7.401
Server Jitter 64.62.153.210 0.280 0.280 0.293 1.478 8.959 9.806 9.806 8.665 9.526 3.171 3.161 ms 0.9069 2.12
Server Jitter 64.62.194.189 0.265 0.265 0.354 1.178 9.156 9.453 9.453 8.801 9.188 3.288 2.960 ms 0.8812 2.203
Server Jitter 73.158.5.1 0.534 0.534 0.992 1.983 9.441 9.542 9.542 8.449 9.009 3.267 3.676 ms 1.396 2.776
Server Jitter SHM(0) 0.107 0.248 0.377 0.939 3.049 5.540 7.673 2.672 5.292 0.981 1.228 ms 3.393 14.94
Server Jitter SHM(1) 55.000 74.000 113.000 250.000 547.000 801.000 1,088.000 434.000 727.000 142.412 279.555 ns 5.386 20.07
Server Offset 162.159.200.1 2.611 2.611 2.727 2.998 4.070 4.092 4.092 1.342 1.481 0.316 3.042 ms 671.4 6076
Server Offset 173.11.101.155 -293.896 -293.896 -198.336 283.617 718.641 860.767 860.767 916.977 1,154.663 257.439 255.458 µs 0.09608 2.774
Server Offset 192.168.1.10 94.101 105.130 126.265 185.125 245.710 255.187 261.050 119.445 150.057 32.598 185.105 µs 116.2 610.1
Server Offset 194.58.202.211 5.855 5.855 6.038 6.420 6.709 6.787 6.787 0.671 0.931 0.184 6.393 ms 3.884e+04 1.317e+06
Server Offset 194.58.202.219 6.596 6.596 6.648 6.868 7.120 7.156 7.156 0.472 0.560 0.142 6.862 ms 1.051e+05 4.963e+06
Server Offset 203.123.48.219 -587.756 -587.756 -467.707 -197.192 -8.673 176.273 176.273 459.034 764.029 161.794 -211.139 µs -19.24 63.54
Server Offset 204.17.205.24 3.618 3.618 3.730 3.970 4.236 4.250 4.250 0.505 0.633 0.141 3.978 ms 2.046e+04 5.611e+05
Server Offset 216.218.192.202 2.653 2.653 2.658 2.900 3.136 3.210 3.210 0.478 0.557 0.138 2.896 ms 8122 1.641e+05
Server Offset 63.145.169.3 -74.214 -74.214 -73.377 -60.516 -10.905 -8.434 -8.434 62.472 65.780 16.706 -56.393 ms -95.43 460.2
Server Offset 64.62.153.210 2.306 2.306 2.435 2.684 3.009 3.045 3.045 0.575 0.739 0.183 2.716 ms 2708 3.813e+04
Server Offset 64.62.194.189 5.498 5.498 5.527 5.801 6.272 6.291 6.291 0.745 0.794 0.221 5.809 ms 1.618e+04 4.105e+05
Server Offset 73.158.5.1 -1.366 -1.366 -0.998 -0.156 0.782 0.962 0.962 1.780 2.328 0.467 -0.124 ms -5.904 16.12
Server Offset SHM(0) -67.107 -66.289 -64.100 -56.332 -50.579 -49.149 -47.650 13.521 17.140 4.516 -57.011 ms -2570 3.557e+04
Server Offset SHM(1) -1,136.000 -885.000 -704.000 -267.000 259.000 437.000 707.000 963.000 1,322.000 286.940 -247.116 ns -11.87 34.49
TDOP 0.470 0.480 0.530 0.800 1.110 1.210 1.450 0.580 0.730 0.205 0.807 34.22 130.4
Temp ZONE0 58.534 58.534 58.534 59.072 60.148 60.686 60.686 1.614 2.152 0.374 59.215 °C
nSats 8.000 8.000 9.000 10.000 12.000 13.000 13.000 3.000 5.000 1.150 9.928 nSat 468.3 3768
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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