[ntp:questions] NTP Performance on WINNT

David Woolley david at ex.djwhome.demon.co.uk.invalid
Mon Jul 27 06:47:55 UTC 2009

Steve Kostecke wrote:

>> I'm just not so sure if I can absolutely count on ntpq to determine
>> time offset of NTP synced machines...
> ntpq does not calculate anything. It merely displays information
> returned from the ntpd it is querying.

I believe that he means the combination of ntpq and and ntpd.  The basic 
problem is that you are trying to mesure a parameter on a system where 
that parameter affects the accuracy of the measurement.

There is also a problem that many other people believe that software 
clock time + offset = UTC time (possibly minus). However, when ntpd is 
operating in the environment in which Dave Mills expects it to operate, 
|UTC - software clock time| << |offset|.

I believe that the parameter the OP actually wants to measure is |UTC - 
software clock time|.  As this is Windows, and Windows doesn't 
interpolate, one would guess that he wants this value at the point of 
the clock tick.

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