Subject: Re: Does PPS_SYNC work ?
To: None <netbsd-users@netbsd.org>
From: Wolfgang S. Rupprecht <wolfgang+gnus20031204T124952@dailyplanet.dontspam.wsrcc.com>
List: netbsd-users
Date: 12/04/2003 13:02:50
tacha@tack.fukui-med.ac.jp (Tatoku Ogaito) writes:
>>> On Wed, 03 Dec 2003 13:30:43 -0800
>  wolfgang+gnus20031203T131256@dailyplanet.dontspam.wsrcc.com (Wolfgang S. Rupprecht) wrote:
>
>  > Since my kernel was missing the com.c stuff too, I just turned off the
>  > kernel kcbind stuff with this in my /etc/ntp.conf .  (It took a lot of
>
> Does it means you don't use PPS ?

The current oncore drivers have the PPS functionality built
in. (Verified by reading the source.)

> How stable your ntp server ?

After the initial startup thrashing ntpq shows that the jitter is
usually around 0.001 - 0.002 uS (parts per million) and offset are
usually under +/- 0.006 uS.

    http://www.wsrcc.com/wolfgang/ftp/ntp-clockjitter.png

(caution: the jitter on that graph is in units of 100nS)

I using ntpd I can clearly track the temperature of my house as the
crystal cools down the PPM changes from 24PPM at 74 degrees F. to
22PPM at 64 degrees F.

Now having said that, I have no independent way to verify that what
ntpq is tilling me is at all valid.  All I know is that the numbers
look quite a bit better than they do with only external ntpd servers.

> I have tried patch included in pr, but pps related information does
> not appeared in ntptime output...  Anyway, I will dig ntp source tomorrow.

You might just want to ignore the patches and run without the kernel
assist for the PPS.

-wolfgang
-- 
Wolfgang S. Rupprecht 		     http://www.wsrcc.com/wolfgang/
       The above "From:" address is valid.  Don't mess with it.