David,

The poll intervals are not managed as you think. The basic consideration is for the discipline loop time constant, which determines the optimum poll interval. The design goal is to move it to the highest value consistent with the anticipated clock frequency wander. A secondary consideration is that the loop not be undersampled should the timing source change. You have constrained the poll interval and time constant when you specify a maxpoll for a source that happens to synchronize the client and that forces all the others to the same value in case one of them is selected.

There small gain in performance when forcing the poll interval to smaller values as against letting the algorithms optimize for ambient conditions. If you are trying to squeeze the optimum performance when doing that, the cost is all the sources are constrained as well.

Dave

David J Taylor wrote:
Richard B. Gilbert wrote:
[]

The reference implementation of ntpd contributes to the deluge in a
small way!   Running a Motorola Oncore as a reference clock causes my
home server to query its internet servers every 16 seconds.  It's
nothing I would do by choice; they serve only as a sanity check on my
Oncore reference clock   There does not appear to be any way of
turning this feature off short of modifying the code.


Agreed. I would like to have my client PCs poll their two LAN servers at 64s and one Internet server at 1024s (also as a sanity check), but it seems that if any LAN server is set to 64s the Internet servers are also polled at 64s intervals.

David


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