[ntp:questions] serialPPS+gpsd+ntpd large offset & jitter
mlichvar at redhat.com
Sun Oct 17 15:52:39 UTC 2010
On Sat, Oct 16, 2010 at 08:24:02AM -0700, M Z wrote:
> I have since run ntp on 2 other similar systems, with and without the gps. It
> seems that the problem is not with the gps but with ntp as there is always a
> large offset and jitter. I have tried some things from the ntp.org problems page
> such as setting HZ=100, setting clocksource to tsc, hpet, and acpi_pm. I do not
> know what to do with acpi so i didn't test that. one of my systems has drift of
> < +-10 which is good. one of the systems is not behind my firewall.
> I have snipped all gps info out below as i only want to know what to do with ntp
Any interesting ntpd messages in syslog?
One additional thing you could try is to disable the kernel discline
by adding "disable kernel" to ntp.conf. If this helps, it's a kernel
bug or possibly a nano/micro mismatch between kernel and ntpd.
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