[ntp:questions] Quick sync between two computers not connected to the internet

unruh unruh at wormhole.physics.ubc.ca
Wed Mar 24 22:30:54 UTC 2010

On 2010-03-24, Rick Jones <rick.jones2 at hp.com> wrote:
>> > On the other hand recent Linux kernels have screwed up the basic
>> > calibration on startup so rebooting a machine is much worse than a
>> > temperature change.  (If they have fixed it recently, I haven't
>> > seen any announcement.  You can fix it by hacking a constant into
>> > your kernel.)
>> Yes, it seems to be fixed. My machines with the more recent kernels
>> are getting about 10PPM out, while the older ones with the
>> calibration problems are more like 100-200PPM out.  and varying by
>> 50PPM or so between boots.
> Which kernel versions are we talking about here, and are the fixes
> backported to distro kernels?

Mandriva 2008.1 has the problems ( kernel 2.6.24 various Mandriva
versions. )
Mandriva 2010.0 ( kernel 2.6.31 various versions) does not seem to have the

I do not think that it is Mandriva backported patches, but the kernel
itself, but could not swear to it.

I have not made an extensive study since chrony does a good job of
compensating for the problems-- fast convergence after reboot-- so I
have not worried about it too much.

> rick jones

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