How to? Use TIMESYNC and log the adjustment

[Steve Fabian]

Vince:
How do I save the adjustment report from TIMESYNC command of sysutils.dll?

Currently I keep a log to learn whether or not my reset interval is too long or too short by using automachron. However, automachron is not Vista/Win7 compatible, and its author disappeared from the 'net. I want to use a command executed periodically. BTW, is it better to have a normally dormant TCC instance (e.g., using DELAY), or to have a service? Automachron is the former...

 

[vefatica]

Do you mean this report?

Client send time: (UTC) 2012/06/01  18:08:19.166
Server recv time: (UTC) 2012/06/01  18:08:19.195
Server send time: (UTC) 2012/06/01  18:08:19.195
Client recv time: (UTC) 2012/06/01  18:08:19.224

You can redirect it to a file.

Use a scheduled task.

I also have a TSYNC.EXE which gives a more useful (?) report if you want to keep track of the adjustments.

tsync time-a.nist.gov  auto
Time server: time-a.nist.gov (129.6.15.28)
 
Estimated round trip time:    85 ms
 
Estimated local time offset: -0.020 seconds

To get this info from the first snippet above, ...

1. the RTT would be (client_rec - client_snd) = 58 ms
2. from the client's point of view, the "middle" of the transaction was at the average of client_snd and client_rec (client_snd plus half of RTT), which was at 18:08:19.194. Calculating similarly, from the server's point of view, the middle was at 18:08:19.195. Assuming the round trip was symmetric in time (the best you can do), the client is 0.001 slow (local offset -0.001). The error in sync'ing the time can be as much as half the RTT (but that would require a very lopsided trip to/from the server).

Time sync programs do all that internally. The timestamps used in NTP use, as units, 2^-32 seconds.