Wall clock accuracy

Eugene Surovegin ebs at ebshome.net
Wed Aug 10 03:02:53 EST 2005


On Tue, Aug 09, 2005 at 09:59:57AM -0700, Eugene Surovegin wrote:
> On Tue, Aug 09, 2005 at 11:57:04AM -0500, Rune Torgersen wrote:
> > > -----Original Message-----
> > > From: Eugene Surovegin [mailto:ebs at ebshome.net] 
> > > Sent: Tuesday, August 09, 2005 11:41
> > > Hmm, if I'm correct this clock drift (130ppm) should be 
> > > handled easily 
> > > by NTPD without stepping clock but with slewing. This is why NTPD 
> > > exists in the first place, so I don't see any reason to change 
> > > the kernel.
> > 
> > NTPD probably handles this correct, but I would like the time to be
> > correct anyways. In our case we might not always have access to a ntpd
> > server, and our input clock is very accurate to begin with.
> 
> Well, NTPD doesn't mean you need to have network connectivity, IIRC if 
> you have exact frequency source, you can add it to NTPD and it'll use 
> it to correct drift.

To rephrase this - Linux kernel already has infrastructure for 
precision time keeping, just use it (even without NTPD) and don't add 
any CPU-specific hacks :).

-- 
Eugene




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