Martin Burnicki wrote: > Hal, > > Hal Murray wrote: > >>How fast does Windows normally slew? I was expecting it to be 500 >>ppm which would take a long time to slew a whole second. > > > Maybe the following is a bit nitpicking, but "Windows" doesn't slew the time > at all. > > Whichever time adjustment service is running, it can modify the tick > adjustment value under Windows as required/desired. > > 500 ppm is a limitation which is specific to ntpd, and maybe operating > systems which implement the kernel clock algorithm developed by Dave Mills, > which is great, BTW. AFAIK the limitation is with respect to the time > synchronization algorithm and the stability of the control loops. > > Windows doesn't implement Dave Mills' clock model, and other time adjustment > services are not limited to the 500 ppm value. > > The article I was referring to can also be found in the NTP questions > mailing list archive: > http://lists.ntp.isc.org/pipermail/questions/2005-October/007296.html > > In the log output you can see that the tick adjustment value is temporarily > changed from 156250 to 78125, so the system time temporarily increases with > half speed only until the time offset introduced by the leap second has > been compensated. >
I hope you mean *decrease* with half speed. You are adding a second not subtracting it so the clock needs to slow down. Danny > > Martin _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
