[Gllug] Fedora/Dell Clock Problems

[Caroline Ford]

On Thu, 2007-03-29 at 20:08 +0100, Nix wrote:
> On 29 Mar 2007, t. clarke stated:
> 
> > My impression has always been that the battery on the Mobo only retains the
> > date/time info in the CMOS whilst powered down.  Once powered up the mobo
> > timer should supply info to the o-s as to real time elapsing.  I think the
> > o-s gets the elapsed time info from the TSC cycle counter on the CPU,  and
> 
> Oh, it's much more nasty than that. There are at least five potential
> clock sources that I know of, all of which have various horrible
> problems. One is nearly useless (0.5s resolution), so there's a choice
> of 4 for gettimeofday() / CLOCK_MONOTONIC clocks. Vojtech Pavlik
> explained it well in <http://lkml.org/lkml/2005/11/18/261>:

My shuttle/nforce2/Ubuntu box gains time when on, but not when off. 

It gains at about 300 secs a day - when it had no net access to correct itself using ntp it was dreadful :(

Mar 30 00:38:55 localhost ntpdate[5717]: step time server 82.211.81.145
offset -297.519466 sec
Mar 30 00:39:11 localhost ntpdate[5785]: step time server 82.211.81.145
offset -0.111680 sec

Bah :(

Caroline

-------------- next part --------------
-- 
Gllug mailing list  -  Gllug at gllug.org.uk
http://lists.gllug.org.uk/mailman/listinfo/gllug