Re: system (not HW) clock advancing really fast

From: Bill Anderson
Date: Mon Feb 16 2004 - 02:50:26 EST


On Mon, 2004-02-16 at 00:45, Michael Frank wrote:
> On Monday 16 February 2004 15:26, Bill Anderson wrote:
> > On Sun, 2004-02-15 at 23:24, Michael Frank wrote:
> > > I had this somtetimes when using ntpd doing step time update
> > > resulting in silly values in /etc/adjtime .
> > >
> > > # mv /etc/adjtime /tmp
> > > # hwclock --systohc
> > >
> > > and see if it goes away.
> >
> > Thanks, though it didn't work. :(
> >
>
> Please check your /etc/ntp/drift , the value in it is
> usually between -30.0 and 30.0
>
> If it is much larger than that, set it to 0.0 and restart ntpd.


Done that, too. in fact, that was my first target.
Along with stop ntpd, sync, clear drift, clear adjtime, sync again, and
restart ntpd. Sorry, should have said that. It's been a *looong* time
since I've posted here.

I just tried some new stuff that is interesting.

MachineA is the one with the problem. MachineB is an identical machine
(as far as two machines can be).

On MachineA I am seeing some interesting things with /proc/interrupts
and the timer interrupt line.

On MachineA:
Over 10 seconds (wall clock):
CPU0: 107 interrupts/second (avg)
CPU1: 102.5 interrupts/second (avg)
[Over 10K interrupts difference between the two]
On MachineB:
Over 10 seconds (wall clock):
CPU0: 46.4 interrupts/second (avg)
CPU1: 45.5 interrupts/second (avg)
[Over 10K interrupts difference between the two]

Now, the CPU differences don't make me blink. However, the slightly more
than double the rate of timer interrupts on the problem machine is
interesting to me. or is it a red herring/blind alley? Especially since
it now seems to be ~2 seconds per second fast.

Cheers, and thanks for the help so far, Michael.

Bill


--
Bill Anderson <banderson@xxxxxx>
Red Hat Certified Engineer

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