NTPsec

C-ntpsec-1-hour-stats

Report generated: Tue Apr 20 14:01:10 2021 UTC
Start Time: Tue Apr 20 13:00:42 2021 UTC
End Time: Tue Apr 20 14:01:10 2021 UTC
Report published: Tue Apr 20 07:01:16 2021 PDT
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 -1,340.000 -881.000 -567.000 -85.000 464.000 672.000 746.000 1,031.000 1,553.000 323.909 -83.815 ns -5.83 16
Local Clock Frequency Offset -5.209 -5.209 -5.209 -5.208 -5.204 -5.204 -5.203 0.0045 0.0052 0.0015 -5.207 ppm -4.497e+10 1.599e+14

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 116.000 119.000 125.000 161.000 299.000 370.000 395.000 174.000 251.000 49.523 175.004 ns 25.97 109

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 21.000 23.000 29.000 79.000 130.000 171.000 178.000 101.000 148.000 31.399 78.022 10e-12 8.268 24.81

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 -1,340.000 -881.000 -567.000 -85.000 464.000 672.000 746.000 1,031.000 1,553.000 323.909 -83.815 ns -5.83 16

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 -5.209 -5.209 -5.209 -5.208 -5.204 -5.204 -5.203 0.0045 0.0052 0.0015 -5.207 ppm -4.497e+10 1.599e+14
Temp ZONE0 56.382 56.382 56.382 56.920 57.458 57.996 57.996 1.076 1.614 0.343 57.010 °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 11.000 11.000 11.000 2.000 3.000 0.714 9.689 nSat 2025 2.593e+04
TDOP 0.620 0.620 0.630 0.700 0.860 1.130 1.130 0.230 0.510 0.107 0.727 213.2 1381

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 1.853 1.853 1.853 1.918 1.952 1.952 1.952 0.098 0.098 0.041 1.908 ms 9.611e+04 4.406e+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 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 2.216 2.216 2.216 2.510 2.581 2.581 2.581 0.365 0.365 0.092 2.482 ms 1.76e+04 4.589e+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 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 2.296 2.296 2.296 2.503 2.871 2.871 2.871 0.575 0.575 0.160 2.526 ms 3301 4.96e+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 -196.061 -196.061 -196.061 190.085 799.795 799.795 799.795 995.856 995.856 278.447 198.424 µs -0.4474 2.457

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 2.406 2.406 2.406 3.067 3.966 3.966 3.966 1.561 1.561 0.532 3.044 ms 120 644.3

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 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 78.937 78.937 90.781 153.975 213.668 225.117 225.117 122.887 146.180 34.420 149.714 µs 47.73 197

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 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 7.756 7.756 7.756 8.118 8.207 8.207 8.207 0.451 0.451 0.131 8.049 ms 2.231e+05 1.354e+07

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 3.488 3.488 3.488 3.676 4.024 4.024 4.024 0.536 0.536 0.146 3.700 ms 1.463e+04 3.592e+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 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 0.421 0.421 0.421 0.610 1.028 1.028 1.028 0.607 0.607 0.177 0.618 ms 24.3 92.79

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 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 2.076 2.076 2.076 2.085 2.210 2.210 2.210 0.134 0.134 0.056 2.113 ms 4.931e+04 1.811e+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 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 3.353 3.353 3.353 3.488 3.592 3.592 3.592 0.239 0.239 0.062 3.483 ms 1.688e+05 9.333e+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 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) -64.843 -64.086 -63.079 -55.331 -49.354 -47.094 -46.594 13.725 16.991 4.469 -56.189 ms -2541 3.506e+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) -1,341.000 -882.000 -568.000 -86.000 465.000 673.000 747.000 1,033.000 1,555.000 324.619 -84.079 ns -5.829 15.98

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 104.131.155.175 169.926 169.926 169.926 306.441 967.735 967.735 967.735 797.809 797.809 348.400 481.367 µs 1.827 3.352

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 1.007 1.007 1.007 2.274 6.989 6.989 6.989 5.982 5.982 1.566 2.516 ms 3.666 11.64

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 95.661 95.661 95.661 428.120 999.578 999.578 999.578 903.917 903.917 264.393 507.882 µs 3.919 9.252

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 1.080 1.080 1.080 1.812 8.390 8.390 8.390 7.310 7.310 3.178 4.088 ms 1.273 2.176

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 8.038 8.038 8.038 8.345 9.014 9.014 9.014 0.976 0.976 0.420 8.486 ms 7161 1.388e+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 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 0.039 0.039 0.053 0.159 8.647 8.710 8.710 8.595 8.672 2.110 0.864 ms 1.251 6.611

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 0.137 0.137 0.137 0.999 9.057 9.057 9.057 8.920 8.920 2.378 1.626 ms 1.521 5.446

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 0.178 0.178 0.178 0.387 8.598 8.598 8.598 8.419 8.419 2.696 1.497 ms 0.783 3.274

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 0.249 0.249 0.249 8.756 8.875 8.875 8.875 8.627 8.627 4.065 4.739 ms 0.4952 1.171

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 0.503 0.503 0.503 0.557 1.467 1.467 1.467 0.964 0.964 0.406 0.764 ms 4.472 11.62

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 0.226 0.226 0.226 0.490 5.229 5.229 5.229 5.003 5.003 1.730 1.297 ms 0.697 2.333

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) 0.113 0.198 0.298 1.175 3.217 5.455 7.131 2.919 5.257 1.017 1.354 ms 3.134 12.83

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) 65.000 86.000 96.000 213.000 505.000 815.000 987.000 409.000 729.000 153.587 248.502 ns 4.077 15.75

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 -5.209 -5.209 -5.209 -5.208 -5.204 -5.204 -5.203 0.0045 0.0052 0.0015 -5.207 ppm -4.497e+10 1.599e+14
Local Clock Time Offset -1,340.000 -881.000 -567.000 -85.000 464.000 672.000 746.000 1,031.000 1,553.000 323.909 -83.815 ns -5.83 16
Local RMS Frequency Jitter 21.000 23.000 29.000 79.000 130.000 171.000 178.000 101.000 148.000 31.399 78.022 10e-12 8.268 24.81
Local RMS Time Jitter 116.000 119.000 125.000 161.000 299.000 370.000 395.000 174.000 251.000 49.523 175.004 ns 25.97 109
Server Jitter 104.131.155.175 169.926 169.926 169.926 306.441 967.735 967.735 967.735 797.809 797.809 348.400 481.367 µs 1.827 3.352
Server Jitter 162.159.200.1 1.007 1.007 1.007 2.274 6.989 6.989 6.989 5.982 5.982 1.566 2.516 ms 3.666 11.64
Server Jitter 162.159.200.123 95.661 95.661 95.661 428.120 999.578 999.578 999.578 903.917 903.917 264.393 507.882 µs 3.919 9.252
Server Jitter 173.11.101.155 1.080 1.080 1.080 1.812 8.390 8.390 8.390 7.310 7.310 3.178 4.088 ms 1.273 2.176
Server Jitter 178.62.68.79 8.038 8.038 8.038 8.345 9.014 9.014 9.014 0.976 0.976 0.420 8.486 ms 7161 1.388e+05
Server Jitter 192.168.1.10 0.039 0.039 0.053 0.159 8.647 8.710 8.710 8.595 8.672 2.110 0.864 ms 1.251 6.611
Server Jitter 194.58.202.211 0.137 0.137 0.137 0.999 9.057 9.057 9.057 8.920 8.920 2.378 1.626 ms 1.521 5.446
Server Jitter 194.58.202.219 0.178 0.178 0.178 0.387 8.598 8.598 8.598 8.419 8.419 2.696 1.497 ms 0.783 3.274
Server Jitter 203.123.48.219 0.249 0.249 0.249 8.756 8.875 8.875 8.875 8.627 8.627 4.065 4.739 ms 0.4952 1.171
Server Jitter 204.123.2.5 0.503 0.503 0.503 0.557 1.467 1.467 1.467 0.964 0.964 0.406 0.764 ms 4.472 11.62
Server Jitter 204.17.205.24 0.226 0.226 0.226 0.490 5.229 5.229 5.229 5.003 5.003 1.730 1.297 ms 0.697 2.333
Server Jitter SHM(0) 0.113 0.198 0.298 1.175 3.217 5.455 7.131 2.919 5.257 1.017 1.354 ms 3.134 12.83
Server Jitter SHM(1) 65.000 86.000 96.000 213.000 505.000 815.000 987.000 409.000 729.000 153.587 248.502 ns 4.077 15.75
Server Offset 104.131.155.175 1.853 1.853 1.853 1.918 1.952 1.952 1.952 0.098 0.098 0.041 1.908 ms 9.611e+04 4.406e+06
Server Offset 162.159.200.1 2.216 2.216 2.216 2.510 2.581 2.581 2.581 0.365 0.365 0.092 2.482 ms 1.76e+04 4.589e+05
Server Offset 162.159.200.123 2.296 2.296 2.296 2.503 2.871 2.871 2.871 0.575 0.575 0.160 2.526 ms 3301 4.96e+04
Server Offset 173.11.101.155 -196.061 -196.061 -196.061 190.085 799.795 799.795 799.795 995.856 995.856 278.447 198.424 µs -0.4474 2.457
Server Offset 178.62.68.79 2.406 2.406 2.406 3.067 3.966 3.966 3.966 1.561 1.561 0.532 3.044 ms 120 644.3
Server Offset 192.168.1.10 78.937 78.937 90.781 153.975 213.668 225.117 225.117 122.887 146.180 34.420 149.714 µs 47.73 197
Server Offset 194.58.202.211 7.756 7.756 7.756 8.118 8.207 8.207 8.207 0.451 0.451 0.131 8.049 ms 2.231e+05 1.354e+07
Server Offset 194.58.202.219 3.488 3.488 3.488 3.676 4.024 4.024 4.024 0.536 0.536 0.146 3.700 ms 1.463e+04 3.592e+05
Server Offset 203.123.48.219 0.421 0.421 0.421 0.610 1.028 1.028 1.028 0.607 0.607 0.177 0.618 ms 24.3 92.79
Server Offset 204.123.2.5 2.076 2.076 2.076 2.085 2.210 2.210 2.210 0.134 0.134 0.056 2.113 ms 4.931e+04 1.811e+06
Server Offset 204.17.205.24 3.353 3.353 3.353 3.488 3.592 3.592 3.592 0.239 0.239 0.062 3.483 ms 1.688e+05 9.333e+06
Server Offset SHM(0) -64.843 -64.086 -63.079 -55.331 -49.354 -47.094 -46.594 13.725 16.991 4.469 -56.189 ms -2541 3.506e+04
Server Offset SHM(1) -1,341.000 -882.000 -568.000 -86.000 465.000 673.000 747.000 1,033.000 1,555.000 324.619 -84.079 ns -5.829 15.98
TDOP 0.620 0.620 0.630 0.700 0.860 1.130 1.130 0.230 0.510 0.107 0.727 213.2 1381
Temp ZONE0 56.382 56.382 56.382 56.920 57.458 57.996 57.996 1.076 1.614 0.343 57.010 °C
nSats 8.000 8.000 9.000 10.000 11.000 11.000 11.000 2.000 3.000 0.714 9.689 nSat 2025 2.593e+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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