[systemd-devel] [PATCH 5/8] timesyncd: use longer PLL time constant

Kay Sievers kay at vrfy.org
Fri Aug 29 09:29:54 PDT 2014

On Wed, Aug 27, 2014 at 4:47 PM, Miroslav Lichvar <mlichvar at redhat.com> wrote:
> The shortest time constant that is stable with the kernel PLL (compiled
> with SHIFT_PLL=2) is about log2 of update interval - 3. Set the constant
> to poll - 2 to make room for one missed update.

Experimentation did show, that the adjustment of the kernel was too
gentle to reach the target time in the desired window, so we made it
more stiff. All timesyncd really cares is that we are not jumping, we
do not really need to smooth out the adjustments.

We would re-check what happens with your patch, I'll hold back
applying this for now.


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