Maarten, You are correct about the frequency, but the statistic of interest here is the phase or offset from one server to another. Accumulated over many poll intervals, the phase does a random walk. In your terms, the integral of a Gaussian distribution is a random walk.
Dave Maarten Wiltink wrote: > "David L. Mills" <[EMAIL PROTECTED]> wrote in message > news:[EMAIL PROTECTED] > > >>>>>Is there also a random backoff after an increase of the polling >>>>>interval? > > >>>>No. However, there is a small dither of a few percent at all poll >>>>intervals to resist self-synchronization. > > >>The natural behavior of a bunch of oscillators near the same frequency >>is to become one giant phase-locked oscillator. Adding a bit of random >>fuzz at each poll turns each oscillator into a mini random-walk which >>breaks up that tendency. The fuzz is not a lot, like 10 percent. > > > Do you mean the dither alluded to above is cumulative? > > I was never much good with statistics and remember only that the > expectation of the offset after N steps in a random walk is sqrt(N) > times the average step size. Not a clue what the distribution might > be. Intuitively, I would be aiming for uniform, and randomly adding > half a polling interval delay when doubling it seemed to me like it > would do that. > > Groetjes, > Maarten Wiltink > > _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
