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Windows-8 with Internet servers alone

Data from PC Torvik, with no LAN servers.  This PC does seem to have some challenges to good timekeeping introduced, perhaps, by the BIOS.  In the results below, this may be the cause of the frequency change from around 02:00 UTC.

Roll over a graph title to see the plot ...

Offset vs. date
Offset vs. time of day
Frequency vs. date
Rel. freq. vs.date
Rel. freq. vs. time of day
Jitter vs. date
Poll interval vs. date
Peerstats statistics Peerstats offset
Peerstats delay
Peerstats dispersion
Peerstats jitter

Windows-8 with LAN servers

Data from a different PC, a portable PC running the release version of Windows-8.  This is a better timekeeper in any case, and here it's syncing to stratum-1 NTP servers (prefer is a FreeBSD server) on the local network.  The minpoll and maxpoll are both set to 5 (32 seconds polling interval).  The Internet servers are still present, but set to a fixed long poll interval (1024 s, minpoll =10)  Here we see much better performance, with jitter averaged jitter between 40 and 80 µs, and offsets between -220 and +320 µs.  The performance is even more surprising as this PC is connected via a Wi-Fi link to the main LAN.

Roll over a graph title to see the plot ...

Offset vs. date
Offset vs. time of day
Frequency vs. date
Rel. freq. vs.date
Rel. freq. vs. time of day
Jitter vs. date
Poll interval vs. date

Here are some snapshot ntpq results.  The jitter on two of the LAN servers seems very high, but the reported ntp jitter is low as can be seen from the graphs above.  At least some of the high jitter is from the Wi-Fi connection, but not all of it, I suspect.

C:\>ntpq -p bergen
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*pixie           .PPS.            1 u   26   32  377    1.301    0.089  43.116
+feenix          .PPS.            1 u    2   32  377    1.301    0.083   0.417
+stamsund        .PPS.            1 u    3   32  377    2.035    0.526  77.736
 uk.pool.ntp.org .POOL.          16 p    - 1024    0    0.000    0.000   0.002
-linnaeus.inf.ed 129.215.64.32    2 u   28 1024  377   32.605    3.957   6.514
-time.mhd.uk.as4 213.229.82.130   3 u  704 1024  377   23.502   11.060   4.196
-dns0.rmplc.co.u 193.62.22.74     2 u  515 1024  377   23.974    3.783  38.570
-ns2.c-it.co     195.66.241.2     2 u  317 1024  377   22.255    3.640  11.516
-ns1.c-it.co     195.66.241.3     2 u  534 1024  377   23.874    4.562   4.750
-protium.cloudfa 80.83.126.67     3 u  547 1024  377   25.710    4.612   1.158

C:\>ntpq -p bergen
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*pixie           .PPS.            1 u    6   32  377    1.301    0.089   0.370
+feenix          .PPS.            1 u   14   32  377    1.301    0.083   0.417
+stamsund        .PPS.            1 u   15   32  377    2.035    0.526  77.736
 uk.pool.ntp.org .POOL.          16 p    - 1024    0    0.000    0.000   0.002
-linnaeus.inf.ed 129.215.64.32    2 u   40 1024  377   32.605    3.957   6.514
-time.mhd.uk.as4 213.229.82.130   3 u  716 1024  377   23.502   11.060   4.196
-dns0.rmplc.co.u 193.62.22.74     2 u  527 1024  377   23.974    3.783  38.570
-ns2.c-it.co     195.66.241.2     2 u  329 1024  377   22.255    3.640  11.516
-ns1.c-it.co     195.66.241.3     2 u  546 1024  377   23.874    4.562   4.750
-protium.cloudfa 80.83.126.67     3 u  559 1024  377   25.710    4.612   1.158

 

Windows-7 with Internet servers alone

Data from PC Ystad, showing LAN servers (until 15:38 UTC Oct 03), Internet servers alone until 19:30 Oct 04, and then back to LAN servers.  One LAN server (192.168.0.3) was left for purely monitoring purposes in the peerstats, it was configured with NOSELECT to ensure that it no part in disciplining the NTP clock.

Roll over a graph title to see the plot ...

Offset vs. date
Offset vs. time of day
Frequency vs. date
Rel. freq. vs.date
Rel. freq. vs. time of day
Jitter vs. date
Poll interval vs. date

Here are the ntpq -p results after running for one day with just Internet servers.

C:\>ntpq -p ystad
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 uk.pool.ntp.org .POOL.          16 p    -   64    0    0.000    0.000   0.977
-ntp.uk.gbit.ws  192.93.2.20      2 u  571 1024  377   40.948   12.089  10.964
-95.172.20.162 ( 129.215.160.240  3 u  378 1024  377   22.956   -4.388   9.264
-b0ff54d9.bb.sky 131.188.3.221    2 u  342 1024  377   44.910    7.057   4.801
-panzer.charliec 245.200.202.182  4 u  332 1024  377   28.999   58.721  31.026
-78.33.40.170 (7 81.2.117.235     2 u  526 1024  377   34.990    9.832  10.149
+dns0.rmplc.co.u 195.66.241.2     2 u  350 1024  377   24.818    0.234  10.879
*ntp.thirdlight. 193.67.79.202    2 u  269 1024  377   24.954    0.769   9.807
+resntp-b-vip.lo 20.139.208.232   4 u  203 1024  377   32.894    6.338   6.968
+indium.cloudfab 195.66.241.2     2 u   61 1024  377   25.918    0.355  12.525

 
Copyright © David Taylor, Edinburgh   Last modified: 2015 Jan 18 at 09:32