[ntp:questions] Bug 2341 - ntpd fails to keep up with clock drift at poll>7

David Lord snews at lordynet.org
Tue Dec 3 02:23:36 UTC 2013


unruh wrote:
> On 2013-12-02, David Lord <snews at lordynet.org> wrote:
>> Martin Burnicki wrote:
>> My server with Sure gps/pps has offset below 3 us other than when
>> nightly cron jobs give a couple of 35 us spikes. From loop_summary
>> over 7 days, typical range for rms offset is 3.9-6.1.
>>
>> Over 7 days my four pool servers have following rms offset ranges
>> ntp0=784-1646, ntp1=405-837, ntp2=310-434, ntp3=586-1270 but there
>> were numerous reboots and ntpd restarts over that period.
>>
>> I want to try using a stable external system clock source, TCXO,
>> OCXO or rubidium laser.
> 
> A sure gps IS a stable external system clock source. What more do you
> want?

? it is a PPS source not a system clock source.

I'd prefer the 35 us blips to go away which would require the PC
to be idle 24/7 or a use of a stable external system clock.

> And those offsets for your pool servers really seem very high. 

did you miss that:
> >> were numerous reboots and ntpd restarts over that period.

but peak offsets are still 300-500 us and I'd prefer if they
were even lower, again requiring a more stable system clock.

What do you think the local offsets should be for a pool server?


David



More information about the questions mailing list