Re: [chrony-dev] SW/HW timestamping on Linux

[Denny Page <dennypage@xxxxxx>]

Setting noselect for all sources seems to have no impact on standard deviation.

Disabling all forms of dynamic tic (CONFIG_HZ_PERIODIC=y) seems to have some effect in reducing the number of “D H”, but does not appear to have much of an impact on the standard deviation. I am returning CONFIG_NO_HZ_IDLE=y.

Denny

On Nov 14, 2016, at 05:35, Miroslav Lichvar <mlichvar@xxxxxxxxxx> wrote:

Another experiment would be to try
configuring all sources with the noselect option and see how much
stddev improves. If it does improve significantly, it would suggest a
problem with the synchronization of the clock. Maybe the kernel is too
slow (the nohz=off option might help) or there is a problem in the
chrony's loop.