ntp debugging output

[Roger Oberholtzer]

On Mon, 22 Mar 2004 20:58:51 -0500
Joel Hammer <joel at hammershome.com> wrote:

> Just so you can see how good life can be with ntp, here
> is my local network time server:
> 
> =LOCAL(0)        127.0.0.0        7   64  377 0.00000  0.000000 0.00093
> *ntp1.usno.navy. 68.33.11.8       1 1024  377 0.04439 -0.000950 0.01483
> =proxy.cc.vt.edu 68.33.11.8       2 1024  377 0.02205 -0.001878 0.01483
> =lennier.cc.vt.e 68.33.11.8       2 1024  277 0.16782  0.072760 0.01547
> 
> And, my formerly bad client:
> 
>      remote           local      st poll reach  delay   offset    disp
> =======================================================================
> *jhammer6.hammer 192.168.1.11     2 1024  377 0.00063 -0.000539 0.01482
> 
> I take this to mean that my network time server is within a
> millisec of a level 1 time server, and my client is within
> a millisec of my network time server.
> 
> Life is good.
> 
> Now, if I just knew what dispersion (jitter) stood for.
> 
> Of course, my computer display (KDE) only shows time in
> intervals of 1 second, so it is pathetically inadequate
> by comparison.  Does anyone know if there is a way to get
> it to display in tenths of a second?

Probably not. It uses the format string from the 'date' command. And I do
not see anything less than seconds. I suspect it is based on the time(2)
system call, which provides seconds.

Keep in mind that a tick on Linux is .01 seconds. So that is really the best
resolution any time event has. Functions like gettimeofday() that contain a
microseconds field are only approximating this. The Linux man page for this
function is rotten. It really only tells the meaning of a parameter that is
not used. Odd approach.

So, if you want better resolution, make a program wrapped around
gettimeofday(2). Maybe you could rework the KDE clock in the panel. Ain't
source great?

-- 
+????????????????????????????+???????????????????????????????+
? Roger Oberholtzer          ?   E-mail: roger at opq.se        ?
? OPQ Systems AB             ?      WWW: http://www.opq.se/  ?
? Erik Dahlbergsgatan 41-43  ?    Phone: Int + 46 8   314223 ?
? 115 34 Stockholm           ?   Mobile: Int + 46 733 621657 ?
? Sweden                     ?      Fax: Int + 46 8   302602 ?
+????????????????????????????+???????????????????????????????+