[CentOS] Date drift and ntpd

[JohnS]

On Fri, 2010-08-13 at 09:47 -0500, Les Mikesell wrote:
> On 8/13/2010 4:06 PM, Jerry Franz wrote:
> > On 8/12/2010 8:03 PM, Les Mikesell wrote:

> Clients should never be 'balky' if you have a stable clock source - 
> perhaps with the exception of some virtual machine situations or 
> seriously bad hardware.
---
The Local Time Source is only as good as the motherboards oscillator
crystal.  It is dependent on how much tolerance, as in frequency the
oscillator is as in PPM (parts per million).  Some being as high as
10ppm for high end hardware.  Some refer to this as jitter/latency.
There is this same nagging problem within radio frequency aslo.  Most
radios are now within 2ppm as is ntp.  The offset being in secs for ntp
and hertz for radio.

http://www.eecis.udel.edu/~ntp/ntpfaq/NTP-s-sw-clocks.htm

John