Yo Dale!
On Wed, 4 Mar 2015 16:43:24 -0500
Dale Smith <dsm...@users.sourceforge.net> wrote:
> Just a pure shot in the dark, but how wide is your PPS pulse? It
> wouldn't be 80mS would it? Like you are syncing to the trailing edge
> instead of the leading edge?
I got one of each. My test bench is crowded and cross-calibrated.
In today's setup, the pulse is 1 mSec, 1 mSec NTP peered to the PtP
master, and the error I see varies from -400 mSec to 800 mSec.
So even if I am on the wrong edge of the master PPS, the two paths
should still be equal offset to UTC.
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97701
g...@rellim.com Tel:+1(541)382-8588
>
> -Dale
>
> On Mon, Mar 2, 2015 at 9:54 PM, Gary E. Miller <g...@rellim.com> wrote:
>
> > Yo Gary!
> >
> > On Mon, 2 Mar 2015 15:39:23 -0800
> > "Gary E. Miller" <g...@rellim.com> wrote:
> >
> > > On Thu, 26 Feb 2015 21:16:21 +0000
> > > "Vick, Matthew" <matthew.v...@intel.com> wrote:
> > >
> > > > One other tidbit is that I210 supports EEE, which can affect
> > > > jitter, although I wouldn't expect it on that level. You can
> > > > try turning this off via ethtool (ethtool --set-eee ethX eee
> > > > off) to see if that helps.
> > >
> > > Ding-ding-ding, I think we might have a winner. That instantly
> > > dropped my offset from -400 mSec to around 1 mSec. That 1 mSec is
> > > well within the confusion that the ntpd PLLs just took. Jitter
> > > went to 1 uSec. Time to hook the PPS back up and get serious.
> >
> > I hooked my PPS back up, let things settle. Checked 'chronyc
> > sources' some more. My hardware timestamp jitter is now down to
> > around a uSec. But I still have a (smaller) persistent offset.
> > Now seems to be running around 80 mSec.
> >
> > My master and slave have similar PPS clocks, so the offset from PPS
> > to timestamp hardware is very real.
> >
> > But, real progress, so I'll try an 82574L on another host. Sadly
> > the 82574L does not support EEE, so that will not help.
> >
> > RGDS
> > GARY
> > ---------------------------------------------------------------------------
> > Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR
> > 97701 g...@rellim.com Tel:+1(541)382-8588
> >
> >
> > ------------------------------------------------------------------------------
> > Dive into the World of Parallel Programming The Go Parallel Website,
> > sponsored
> > by Intel and developed in partnership with Slashdot Media, is your
> > hub for all
> > things parallel software development, from weekly thought
> > leadership blogs to
> > news, videos, case studies, tutorials and more. Take a look and
> > join the conversation now. http://goparallel.sourceforge.net/
> > _______________________________________________
> > Linuxptp-devel mailing list
> > Linuxptp-devel@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
> >
------------------------------------------------------------------------------
Dive into the World of Parallel Programming The Go Parallel Website, sponsored
by Intel and developed in partnership with Slashdot Media, is your hub for all
things parallel software development, from weekly thought leadership blogs to
news, videos, case studies, tutorials and more. Take a look and join the
conversation now. http://goparallel.sourceforge.net/
_______________________________________________
Linuxptp-devel mailing list
Linuxptp-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
