NTPsec

C-ntpsec-24-hour-stats

Report generated: Tue Apr 20 13:02:01 2021 UTC
Start Time: Mon Apr 19 13:02:01 2021 UTC
End Time: Tue Apr 20 13:02:01 2021 UTC
Report published: Tue Apr 20 06:02:09 2021 PDT
Report Period: 1.0 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 -1,403.000 -979.000 -707.000 -57.000 648.000 927.000 1,811.000 1,355.000 1,906.000 419.423 -48.091 ns -4.573 11.39
Local Clock Frequency Offset -5.203 -5.197 -5.165 -5.081 -4.994 -4.992 -4.991 0.172 0.205 0.063 -5.082 ppm -5.366e+05 4.361e+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 79.000 101.000 122.000 175.000 262.000 326.000 525.000 140.000 225.000 46.029 181.564 ns 35.65 149.1

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 24.000 34.000 42.000 94.000 215.000 331.000 475.000 173.000 297.000 57.435 105.306 10e-12 5.021 19.87

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 -1,403.000 -979.000 -707.000 -57.000 648.000 927.000 1,811.000 1,355.000 1,906.000 419.423 -48.091 ns -4.573 11.39

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 -5.203 -5.197 -5.165 -5.081 -4.994 -4.992 -4.991 0.172 0.205 0.063 -5.082 ppm -5.366e+05 4.361e+07
Temp ZONE0 56.920 56.920 57.458 58.534 60.148 60.148 60.148 2.690 3.228 0.826 58.577 °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 3.000 7.000 7.000 9.000 11.000 12.000 13.000 4.000 5.000 1.400 9.364 nSat 200.8 1237
TDOP 0.500 0.560 0.590 0.840 1.210 1.570 2.020 0.620 1.010 0.214 0.870 39.64 171.3

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 104.131.155.175

peer offset 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 104.131.155.175 1.674 1.674 1.885 2.185 2.576 4.878 4.878 0.691 3.205 0.400 2.211 ms 110.8 654

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 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 2.084 2.180 2.296 2.545 2.820 3.039 4.739 0.523 0.859 0.223 2.560 ms 1187 1.296e+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 162.159.200.123

peer offset 162.159.200.123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 162.159.200.123 2.052 2.199 2.322 2.564 2.853 2.992 3.055 0.530 0.793 0.164 2.582 ms 3231 4.821e+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 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 -1.607 -1.517 -0.696 0.235 0.769 1.280 1.369 1.465 2.798 0.461 0.185 ms -3.14 10.87

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 178.62.68.79

peer offset 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 178.62.68.79 0.670 0.670 1.557 2.769 5.072 5.568 5.568 3.515 4.899 0.951 2.974 ms 16.42 54.59

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 -93.463 65.123 90.435 159.253 323.720 424.777 487.417 233.285 359.654 67.685 167.143 µs 9.522 37.79

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 2.188 3.522 3.662 7.823 8.335 8.489 8.711 4.672 4.967 1.972 6.395 ms 17.55 52.78

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 1.857 1.889 2.024 3.752 4.061 4.319 6.563 2.037 2.430 0.673 3.545 ms 89.38 428.5

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

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

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

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



Server Offset 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 0.154 0.282 0.426 0.668 0.948 1.042 1.112 0.521 0.760 0.157 0.671 ms 45.01 183.7

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

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

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

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



Server Offset 204.123.2.5

peer offset 204.123.2.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Offset 204.123.2.5 1.902 1.909 1.990 2.181 2.383 2.465 2.631 0.393 0.556 0.131 2.185 ms 3928 6.249e+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 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 3.026 3.142 3.274 3.570 3.852 4.051 4.163 0.578 0.910 0.180 3.562 ms 6636 1.254e+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(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) -68.509 -64.757 -62.685 -55.083 -47.228 -45.282 -43.572 15.458 19.475 4.688 -55.077 ms -2111 2.74e+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) -1,404.000 -980.000 -708.000 -58.000 649.000 928.000 1,812.000 1,357.000 1,908.000 420.193 -48.187 ns -4.573 11.38

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 104.131.155.175

peer jitter 104.131.155.175 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 104.131.155.175 0.000 0.000 0.260 1.504 8.860 12.561 12.561 8.600 12.561 3.219 3.039 ms 1.064 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 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 0.147 0.188 0.265 1.592 9.126 12.525 12.752 8.861 12.337 2.961 2.870 ms 1.367 3.777

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 162.159.200.123

peer jitter 162.159.200.123 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 162.159.200.123 0.113 0.164 0.247 1.171 8.941 12.687 15.499 8.694 12.523 3.366 2.878 ms 0.9521 3.152

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 0.384 0.454 0.756 1.772 9.741 22.905 39.691 8.985 22.451 4.306 3.638 ms 2.976 20.45

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 178.62.68.79

peer jitter 178.62.68.79 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 178.62.68.79 0.299 0.299 0.522 1.572 11.176 77.012 77.012 10.654 76.713 11.159 4.621 ms 3.103 19.77

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 0.023 0.035 0.061 0.187 8.686 8.894 14.394 8.625 8.859 2.570 1.301 ms 0.7949 4.579

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 0.129 0.160 0.224 1.318 9.354 12.362 12.715 9.131 12.202 3.091 2.714 ms 1.078 3.31

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 0.231 0.267 0.441 1.699 9.480 15.257 17.966 9.038 14.990 3.425 3.352 ms 1.523 4.952

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 0.000 0.051 0.244 1.625 11.429 13.094 21.001 11.185 13.043 3.532 3.028 ms 1.338 5.218

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 204.123.2.5

peer jitter 204.123.2.5 plot

Percentiles...... Ranges...... Skew- Kurt-
Name Min1%5%50%95% 99%Max   90%98%StdDev  MeanUnits nessosis
Server Jitter 204.123.2.5 0.169 0.196 0.283 1.427 8.799 9.154 72.220 8.516 8.959 6.332 3.183 ms 7.323 80.65

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 0.156 0.176 0.256 0.948 8.828 10.008 13.420 8.572 9.832 2.724 2.183 ms 1.191 3.973

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) 0.130 0.225 0.337 0.929 3.030 5.684 8.952 2.693 5.460 0.992 1.202 ms 3.48 16.07

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

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

RMS Jitter is field 8 in the peerstats log file.



Server Jitter 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) 41.000 70.000 100.000 215.000 517.000 707.000 1,483.000 417.000 637.000 136.046 250.125 ns 4.808 18.41

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 -5.203 -5.197 -5.165 -5.081 -4.994 -4.992 -4.991 0.172 0.205 0.063 -5.082 ppm -5.366e+05 4.361e+07
Local Clock Time Offset -1,403.000 -979.000 -707.000 -57.000 648.000 927.000 1,811.000 1,355.000 1,906.000 419.423 -48.091 ns -4.573 11.39
Local RMS Frequency Jitter 24.000 34.000 42.000 94.000 215.000 331.000 475.000 173.000 297.000 57.435 105.306 10e-12 5.021 19.87
Local RMS Time Jitter 79.000 101.000 122.000 175.000 262.000 326.000 525.000 140.000 225.000 46.029 181.564 ns 35.65 149.1
Server Jitter 104.131.155.175 0.000 0.000 0.260 1.504 8.860 12.561 12.561 8.600 12.561 3.219 3.039 ms 1.064 2.776
Server Jitter 162.159.200.1 0.147 0.188 0.265 1.592 9.126 12.525 12.752 8.861 12.337 2.961 2.870 ms 1.367 3.777
Server Jitter 162.159.200.123 0.113 0.164 0.247 1.171 8.941 12.687 15.499 8.694 12.523 3.366 2.878 ms 0.9521 3.152
Server Jitter 173.11.101.155 0.384 0.454 0.756 1.772 9.741 22.905 39.691 8.985 22.451 4.306 3.638 ms 2.976 20.45
Server Jitter 178.62.68.79 0.299 0.299 0.522 1.572 11.176 77.012 77.012 10.654 76.713 11.159 4.621 ms 3.103 19.77
Server Jitter 192.168.1.10 0.023 0.035 0.061 0.187 8.686 8.894 14.394 8.625 8.859 2.570 1.301 ms 0.7949 4.579
Server Jitter 194.58.202.211 0.129 0.160 0.224 1.318 9.354 12.362 12.715 9.131 12.202 3.091 2.714 ms 1.078 3.31
Server Jitter 194.58.202.219 0.231 0.267 0.441 1.699 9.480 15.257 17.966 9.038 14.990 3.425 3.352 ms 1.523 4.952
Server Jitter 203.123.48.219 0.000 0.051 0.244 1.625 11.429 13.094 21.001 11.185 13.043 3.532 3.028 ms 1.338 5.218
Server Jitter 204.123.2.5 0.169 0.196 0.283 1.427 8.799 9.154 72.220 8.516 8.959 6.332 3.183 ms 7.323 80.65
Server Jitter 204.17.205.24 0.156 0.176 0.256 0.948 8.828 10.008 13.420 8.572 9.832 2.724 2.183 ms 1.191 3.973
Server Jitter SHM(0) 0.130 0.225 0.337 0.929 3.030 5.684 8.952 2.693 5.460 0.992 1.202 ms 3.48 16.07
Server Jitter SHM(1) 41.000 70.000 100.000 215.000 517.000 707.000 1,483.000 417.000 637.000 136.046 250.125 ns 4.808 18.41
Server Offset 104.131.155.175 1.674 1.674 1.885 2.185 2.576 4.878 4.878 0.691 3.205 0.400 2.211 ms 110.8 654
Server Offset 162.159.200.1 2.084 2.180 2.296 2.545 2.820 3.039 4.739 0.523 0.859 0.223 2.560 ms 1187 1.296e+04
Server Offset 162.159.200.123 2.052 2.199 2.322 2.564 2.853 2.992 3.055 0.530 0.793 0.164 2.582 ms 3231 4.821e+04
Server Offset 173.11.101.155 -1.607 -1.517 -0.696 0.235 0.769 1.280 1.369 1.465 2.798 0.461 0.185 ms -3.14 10.87
Server Offset 178.62.68.79 0.670 0.670 1.557 2.769 5.072 5.568 5.568 3.515 4.899 0.951 2.974 ms 16.42 54.59
Server Offset 192.168.1.10 -93.463 65.123 90.435 159.253 323.720 424.777 487.417 233.285 359.654 67.685 167.143 µs 9.522 37.79
Server Offset 194.58.202.211 2.188 3.522 3.662 7.823 8.335 8.489 8.711 4.672 4.967 1.972 6.395 ms 17.55 52.78
Server Offset 194.58.202.219 1.857 1.889 2.024 3.752 4.061 4.319 6.563 2.037 2.430 0.673 3.545 ms 89.38 428.5
Server Offset 203.123.48.219 0.154 0.282 0.426 0.668 0.948 1.042 1.112 0.521 0.760 0.157 0.671 ms 45.01 183.7
Server Offset 204.123.2.5 1.902 1.909 1.990 2.181 2.383 2.465 2.631 0.393 0.556 0.131 2.185 ms 3928 6.249e+04
Server Offset 204.17.205.24 3.026 3.142 3.274 3.570 3.852 4.051 4.163 0.578 0.910 0.180 3.562 ms 6636 1.254e+05
Server Offset SHM(0) -68.509 -64.757 -62.685 -55.083 -47.228 -45.282 -43.572 15.458 19.475 4.688 -55.077 ms -2111 2.74e+04
Server Offset SHM(1) -1,404.000 -980.000 -708.000 -58.000 649.000 928.000 1,812.000 1,357.000 1,908.000 420.193 -48.187 ns -4.573 11.38
TDOP 0.500 0.560 0.590 0.840 1.210 1.570 2.020 0.620 1.010 0.214 0.870 39.64 171.3
Temp ZONE0 56.920 56.920 57.458 58.534 60.148 60.148 60.148 2.690 3.228 0.826 58.577 °C
nSats 3.000 7.000 7.000 9.000 11.000 12.000 13.000 4.000 5.000 1.400 9.364 nSat 200.8 1237
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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