On Mon, Jan 26, 2015 at 06:45:58PM +0100, Terje Mathisen wrote: > Miroslav Lichvar wrote: > >Here is a test showing error between two clients of a server > >smearing.a large offset. With the cosine function you can see a large > >spike when smearing started. > > > >https://mlichvar.fedorapeople.org/tmp/smear_cos.png > >https://mlichvar.fedorapeople.org/tmp/smear_sinx.png > > > This seems wrong!?! > > First of all, you seem to extend the smearing over a million seconds or so? > I.e. 10-15 days?
Yes. > How large is the adjustment to be smeared out? 10000 seconds. It was a test to see how useful is smearing when bringing an isolated network back to UTC in a controlled manner. > The google cosine approach starts with a derivate of zero and ends the same > way, I really can't see how that leads to that huge (more than 128 ms!) > spike at the start? The frequency is changing too quickly at start (2nd derivative is at the maximum) and the clients don't have a chance to shorten their polling interval to better track the server. The point is that there are better functions than cosine for this. -- Miroslav Lichvar _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions