Port-vax archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: PSA: Clock drift and pkgin



Hi!

On Thu, 2023-12-21 10:44:22 +0000, Maciej W. Rozycki <macro%orcam.me.uk@localhost> wrote:
> On Wed, 20 Dec 2023, Maciej W. Rozycki wrote:
> > > > > Did anyone actually report results running on a 4000/60?
> > > >   Me, earlier on in this thread.
> > > Great. Sorry that I didn't remember. How did the clock behave for you?
> >  See my first message in this thread, in reply to one of yours actually.
> 
>  NB lizzie has now finally dropped sync with NTP again, a week after I 
> resynced it by hand:

two days ago:

> ntpq> pe
>      remote           refid      st t when poll reach   delay   offset  jitter
> ==============================================================================
>  [...]           [...]            3 u  744 1024    7   25.923  -32.162  32.142
>  [...]           [...]            3 u  751 1024    7   20.404    0.276  48.403
>  [...]           [...]            2 u  742 1024    7   19.342  -66.966  52.595
>  [...]           [...]            1 u  743 1024    7   25.694   -6.129  52.045
> ntpq> pe
>      remote           refid      st t when poll reach   delay   offset  jitter
> ==============================================================================
>  [...]           [...]            3 u   40 1024   17   25.733  -190.71 287.373
>  [...]           [...]            3 u    3 1024   17   21.716  -160.87 315.647
>  [...]           [...]            2 u 1014 1024    7   18.846  -221.87  30.274
>  [...]           [...]            1 u   19 1024   17   25.443  -197.80 293.301

yesterday:

> ntpq> pe
>      remote           refid      st t when poll reach   delay   offset  jitter
> ==============================================================================
>  [...]           [...]            3 u  871 1024  377   26.259  -20033. 2180.79
>  [...]           [...]            3 u  835 1024  377   21.561  -19558. 1769.50
>  [...]           [...]            2 u  863 1024  377   18.561  -19542. 1774.29
>  [...]           [...]            1 u  635 1024  377   26.070  -20149. 2232.44
> ntpq> pe
>      remote           refid      st t when poll reach   delay   offset  jitter
> ==============================================================================
>  [...]           [...]            3 u  578 1024  377   26.065  -21509. 2189.34
>  [...]           [...]            3 u  564 1024  377   21.320  -21019. 1767.10
>  [...]           [...]            2 u  555 1024  377   18.687  -21521. 2208.66
>  [...]           [...]            1 u  356 1024  377   25.525  -21128. 1794.22

today:

> ntpq> pe
>      remote           refid      st t when poll reach   delay   offset  jitter
> ==============================================================================
>  [...]           [...]            3 u  261 1024  377   26.436  -50773. 2181.67
>  [...]           [...]            3 u  235 1024  377   22.300  -50785. 2183.03
>  [...]           [...]            2 u  284 1024  377   19.222  -50763. 2165.15
>  [...]           [...]            1 u   57 1024  377   26.263  -50390. 1765.14
> ntpq>

Looking at the numbers, I wonder about multiple issues here. Why did
the jitter values rise up that much, while the delay keeps its value?

Why was two days ago's reachability so limited?

Did it max out its PLL frequency (`kerninfo` or `rv` will show that)?

...and finally: Why didn't ntpd react with increasing the poll
interval?


Do you, by chance, know the approximate times when you fetched
"yesterdays" and "todays" numbers? Between that time, it drifted away
by some 30 sec, but over what interval?

MfG, JBG

-- 

Attachment: signature.asc
Description: PGP signature



Home | Main Index | Thread Index | Old Index