NTP on amd74 + powernow issues

[Peter Jeremy]

On Fri, Apr 04, 2008 at 07:46:05PM +0200, Guido van Rooij wrote:
>I've got a amd64 system where I;m using powernow. I am using th i8254
>timecounter.

I'm using ACPI-fast on amd64 without problems.  i8254 should not be
affected by PowerNow! but ACPI-fast should be listed as preferable.
Do you have a particular reason for using the i8254?

>Especially the largers resets (+10 seconds) are annoying as e.g. dovecot
>bails out.
>
>Any clue on how this could be fixed?

Any time resets are abnormal.  There's nothing obviously wrong with
your NTP servers.  I have had problems in the past with the ntpd PLL
saturating and demonstrating symptoms similar to what you are seeing.

What does your ntp.drift contain?  My guess is that it's either +500
or -500.  If this is true, I suggest you:
- stop ntpd
- delete ntp.drift
- enable loopstats collection in your ntp.conf (optional)
- run "ntptime -f 0"
- run "/etc/rc.d/ntpdate start"
- run "/etc/rc.d/ntpd start"

This will force ntpd to re-calibrate and, hopefully, it will stabilise,
though this can take a day or so.

You can monitor the NTP PLL behaviour via the loopstats file.

-- 
Peter Jeremy
Please excuse any delays as the result of my ISP's inability to implement
an MTA that is either RFC2821-compliant or matches their claimed behaviour.
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