"normal" clock drift

[Lennart Sorensen]

On Fri, Mar 01, 2013 at 04:01:42PM -0500, Christopher Browne wrote:
> My phone regularly drifts by ~1s; the ClockSync app often adjusts,
> when it gets onto a
> network, by around 1s.
> 
> I don't see any bumps in my logs at home lately; I would expect fairly
> similar drift on
> an undisciplined clock (e.g. - one not regularly getting touched by a
> continuous NTP
> daemon).  The crystals commonly on PC clocks aren't spectacularly precise, and
> things have cheapened since the "real UNIX(tm) server days", where the vendors
> *sometimes* paid attention to clock precision.
> 
> If you care about precise time, you really should install ntpd, and have it
> continuously discipline your clock, as you can surely, on modern
> hardware, afford
> the ~1MB of RSS consumed by ntpd.

ntpd running continuously certainly works most of the time.  I have
only encountered one system where that didn't work.  ntpd declared the
sytem unusable.  It's clock drifted 5 to 10 minutes per day, and not in
any consistent direction.

Everytime ntpd thought it had the drift right, it would overshoot and
have to change directions.

-- 
Len Sorensen
--
The Toronto Linux Users Group.      Meetings: http://gtalug.org/
TLUG requests: Linux topics, No HTML, wrap text below 80 columns
How to UNSUBSCRIBE: http://gtalug.org/wiki/Mailing_lists